cant upgrade this version of os x because a new version is installed

You may need to replace the hard drive cable which might have been the cause of your original issue when you used the TimeMachine backup. The hard drive cable on the 13" MBPro 2012 had a high rate of failure. I've seen it allow the copy stage of an OS install, but fail when rebooting to finish.

As for the error message about not being able to upgrade, it appears it is referencing your USB Mojave installer from what I can see in your original screenshot which you cannot upgrade.

There is an issue in the data transfer as it never completes (or perhaps even begin). Assuming your TimeMachine backup is functional and there is no issue with the drive, then I would really suspect the MBPro's hard drive cable.

What is the make & model of the new SSD?

In the mean time you could boot into Recovery Mode. If you cannot manage users in Recovery Mode, then you could try using Migration Assistant and only select your User Folder to minimize the amount of data to transfer. If there is a lot of data in your User Folder, then I would uncheck Music, Pictures, etc. which may have GBs of data and only allow the account & it's settings to transfer. Migration Assistant may prompt you about deleting the User Folder on the new SSD since you cannot have to identical users on a system.

That is correct. From your image you have only one available drive. It's listed in your image as:

1 TB Mercury Electra 6G...

Macintosh HD

The volume on which you will install macOS is Macintosh HD which is on the SSD. It should appear in the Installer as the default destination disk. You should erase Macintosh HD before installing macOS. Otherwise, the installer will not allow you to overwrite a disk with data on it.

Are you actually trying to install from a bootable USB flash drive? I see it listed in your image as Install macOS Mojave. If so, then the procedure that I have outlined for you previously will be slightly different. The flash drive installer may open automatically to the Utility Menu. Or it may open automatically to the installation window directly.

Please do the following:

Internet/Network Recovery of El Capitan or Later on a Clean Disk

     If possible back up your files before proceeding.

1. Restart the computer. Immediately after the chime hold down the (Command-Option-R) keys until a globe appears.
2. The Utility Menu will appear in from 5-20 minutes. Be patient.
3. Select Disk Utility and click on the Continue button.
4. When Disk Utility loads select the drive (usually, the out-dented entry) from the side list.
5. Click on the Erase tab in Disk Utility's main window. A panel will drop down.
6. Set the partition scheme to GUID.
7. Set the Format type to APFS (SSDs only) or Mac OS Extended (Journaled.)
8. Click on the Apply button, then click on the Done button when it activates.
9. Quit Disk Utility and return to the Utility Menu.
10. Select Reinstall OS X and click on the Continue button.

This should install the latest version of macOS. Since you will be erasing the drive you may be able to use your Time Machine backup to migrate your Home folder to the new installation while in the Setup Assistant that appears during the initial startup. Be sure to have your Time Machine drive connected. The Setup Assistant will try migrating your Home folder from the most recent backup. The Setup Assistant will first ask you to create a new Admin account. Please don't use the same username that you used for your Home folder, otherwise Setup Assistant will ask for a different username.

May I assume you wish to install on Macintosh HD shown in your pic? If so:

Internet/Network Recovery of El Capitan or Later on a Clean Disk

     If possible back up your files before proceeding.

1. Restart the computer. Immediately after the chime hold down the (Command-Option-R) keys until a globe appears.
2. The Utility Menu will appear in from 5-20 minutes. Be patient.
3. Select Disk Utility and click on the Continue button.
4. When Disk Utility loads select the drive (1TB Mercury Electra...) from the side list.
5. Click on the Partition tab in Disk Utility's main window toolbar. 
6. Set the number of partitions to one (1) from the Partition Scheme drop-down menu.
7. Set the Format type to Mac OS Extended (Journaled.)
8. Click on the Apply button.
9. Quit Disk Utility and return to the Utility Menu.
10. Select Install OS X and click on the Continue button.

Now, I am assuming you are using the Network Recovery that is outlined above.

OK, then follow the procedure I outlined earlier for a Network Recovery. If you still wish to try using the flash drive and still have the Mojave installer then see the following.

Bootable USB Installers for OS X Mavericks, Yosemite, El Capitan, and Sierra

First, review this introductory article: Create a bootable installer for macOS. Second, read this How To outline for creating a bootable macOS installer. Simply use the Terminal command by copying and pasting the command line for the version of macOS from the list below. You will need an 8GB or larger USB flash drive that has been partitioned and formatted for use with OS X as well as an installer for the desired macOS version that you have previously downloaded from the App Store.

Drive Partition and Format

1. Open Disk Utility in the Utilities' folder.
2. After Disk Utility loads select the drive (out-dented entry with the mfg.'s ID and size) from the side list.
3. Click on the Erase tab in the Disk Utility toolbar. Name the drive, "MyVolume". <---- IMPORTANT!
4. In the drop down panel set the partition scheme to GUID. Set the Format type to Mac OS Extended (Journaled.)
5. Click on the Apply button and wait for the Done button to activate. When it does click on it.
6. Quit Disk Utility.

Create InstallerOpen the Terminal in the Utilities' folder. Choose the appropriate command line (in red) depending upon what OS X installer you want. Paste that entire command line from below at the Terminal's prompt:

*Command for macOS Mojave:sudo /Applications/Install\ macOS\ Mojave.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

*Command for macOS High Sierra:sudo /Applications/Install\ macOS\ High\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume

Command for macOS Sierra:sudo /Applications/Install\ macOS\ Sierra.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ macOS\ Sierra.app

Command for El Capitan:sudo /Applications/Install\ OS\ X\ El\ Capitan.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ El\ Capitan.app

Command for Yosemite:sudo /Applications/Install\ OS\ X\ Yosemite.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ Yosemite.app

Command for Mavericks:sudo /Applications/Install\ OS\ X\ Mavericks.app/Contents/Resources/createinstallmedia --volume /Volumes/MyVolume --applicationpath /Applications/Install\ OS\ X\ Mavericks.app

Press RETURN. You will be asked for your admin password. It will not echo to the Terminal window. Then press RETURN again. Wait for the return of the Terminal prompt signifying the process has completed. It takes quite some time to finish. Be patient.

* If your Mac is using macOS Sierra or earlier, include the --applicationpath argument. The Sierra and El Capitan commands show the proper format of this argument.

The bootable installer can be used to install the selected version of macOS. Shut the computer down. Insert your flash drive into a USB port. Start the computer like so:

Boot Using OPTION key

1. Restart the computer.
2. Immediately after the chime press and hold down the  "OPTION" key.
3. Release the key when the Boot Manager screen appears.
4. Select the disk icon for the USB flash drive.
5. Click on the arrow button under the disk icon.