Apps not working , Mac is unstable after upgrading to Catalina

A Troubleshooting Procedure that may Fix Problems with macOS El Capitan or Later

You should try each, one at a time, then test to see if the problem is fixed before going on to the next.

    Be sure to backup your files before proceeding if possible.

1. Shutdown the computer, wait 30 seconds, restart the computer.
2. Disconnect all third-party peripherals.
3. Resetting your Mac's PRAM and NVRAM
4. Reset the System Management Controller (SMC)
5. Reset your Startup Disk and Sound preferences, if needed, after resetting the PRAM.
6. Test in safe mode to see if the problem persists, then restart normally.  Use safe mode to isolate issues with your Mac and Playing Safe - what does Safe mode do?
7. Repair the disk by booting from the Recovery HD. Immediately after the chime hold down the Command and R keys until the Utility Menu appears. Choose Disk Utility and click on the Continue button. Select the indented (usually, Macintosh HD) volume entry from the side list.  Click on the First Aid button in the toolbar. Wait for the Done button to appear. Quit Disk Utility and return to the Utility Menu. Restart the computer from the Apple Menu.
8. Repair permissions on the Home folder: Resolve issues caused by changing the permissions of items in your home folder.
9. Create a New User Account Open Users & Groups preferences. Click on the lock icon and enter your Admin password when prompted. On the left under Current User click on the Add [+] button under Login Options. Setup a new Admin user account. Upon completion log out of your current account then log into the new account. If your problems cease, then consider switching to the new account and transferring your files to it - Transferring files from one User Account to another.
10. Reinstall OS X by booting from the Recovery HD using the Command and R keys. When the Utility Menu appears select Install OS X then click on the Continue button.
11. Erase and Install OS X Restart the computer. Immediately after the chime hold down the Command and R keys until the Apple logo appears. When the Utility Menu appears:

     1. Select Disk Utility from the Utility Menu and click on the Continue button.

     2. When Disk Utility loads select the drive (out-dented entry) from the Device list.

     3. Click on the Erase button in Disk Utility's toolbar. A panel will drop down.

     4. Set the Format type to APFS (for SSDs only) or Mac OS Extended (Journaled.)

     5. Click on the Apply button, then wait for the Done button to activate and click on it.

     6. Quit Disk Utility and return to the Utility Menu.

     7. Select Install OS X and click on the Continue button.

We have to ask you to reinstall because the upgrade was not installed properly to begin with. I'm not blaming you for anything but if the underlying system was dysfunctional, then the upgraded system will be worse. For future reference:

Before You Upgrade macOS

1. Fix any problems before upgrading.
2. Run First Aid in Disk Utility while booted from your Recovery HD.
3. Backup. Make a bootable clone using CarbonCopy Cloner or use TimeMachine.
4. Be sure your startup disk has 18-20GB of free space during the installation.
5. Upgrade third-party software for compatibility. See App Compatibility Table - RoaringApps. If you have mission critical software, then DO NOT upgrade until you know that software is compatible with the version of macOS you are about to install.
6. Disconnect all third-party peripherals.
7. Download the installer which will be in the Applications folder. Quit the installer after it opens, then make a copy of the installer and save it in the Downloads folder. The one in the Applications folder will be deleted after a successful installation.
8. The download is large, anywhere between 5 and 9GBs. It takes time to complete. Be patient.
9. Double-click on the installer in the Applications folder. Click on the start button to begin the installation.

I suggest you mMake an appointment at the Apple Genius Bar for service. If you need to find an Apple Store - Find a Store - Apple. Also, see How to find your nearest Apple Authorized Service Provider (AASP) or Distributor (AAD).

That's what we call a "clean install". The different between a clean install and an "in-place upgrade" is that the upgrade carries all of the information from the old operating system into the upgraded OS. Over time (unexpected power losses, crashed apps, etc.), flotsam and jetsam get into the works, causing the same issues you described. This is a universal problem, affecting Windows users more than Mac users, but both have similar symptoms.

One thing I remember from my Apple training (WAAAAY back in the 80's), is that anytime you update the OS, you should also zap the PRAM. The PRAM is a battery-backed up chip inside your Mac; it stands for Preferences RAM). This is where things like your Startup Disc, clock, etc. are stored when your PC is off. When you update the OS, sometimes the PRAM needs to be reset, so it is forced to grab the new values from the OS. Even more so, modern Macs update the computer's firmware chips as well, so I think it's even more important to zap the PRAM whenever my Mac acts "goofy". As in, my sound prefs don't hold or my fan starts to run all of the time. Actually, the fan is a symptom the SMC chip needs to be reset, but now I'm getting all techie. Just know that there are two chips that, when reset, solve about 80% of a Mac's mysterious, sudden issues.

About once every couple of months, I zap the PRAM and reset the SMC:

Zap the PRAM:

https://support.apple.com/en-us/HT204063

Reset the SMC:

https://support.apple.com/en-us/HT201295

William

From the report:

Configuration Files:

/etc/hosts - Count: 0 - Corrupt!

About etc/host/file:

https://discussions.apple.com/docs/DOC-8091

I see you recently installed CleanMyMac4. Did your problems start after that install?