Unable to update pre-installed apps

Those apps along with macOS were all obtained by the previous owner with his/her Apple ID to which they are all tied. The previous owner should have restored the computer to its factory state. You will have to do so, unless the prior owner is willing to give you his/her Apple ID and password.

What you must do is completely wipe the drive and install the original version of macOS that came pre-installed from the factory. If your purchase is from Late-2011 or later, then here's what to do: Factory reset of your Mac.

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

1. Restart the computer. Immediately, at or before the chime, hold down the (Command-Option-Shift-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 target drive (out-dented entry w/type and size) from the side list.
5. Click on the Erase button in Disk Utility's toolbar. A panel will drop down.
6. Set the partition scheme to GUID.
7. Set the Format type to APFS (SSDs, only if installing Mojave or Catalina ) or Mac OS Extended, (Journaled.)
8. Provide a volume name, usually "Macintosh HD."
9. Click on the Apply button, then click on the Done button when it activates.
10. Quit Disk Utility and return to the Utility Menu.
11. Select Install OS X and click on the Continue button.

This will install the original version of macOS that was pre-installed at the factory. It will boot the computer into the Setup Assistant in which you will set your Apple ID as the registrant and create your own Admin account, and username and password.

If you have any problems with the above, don't hesitate to post back, here, a description of the problem. If you have a computer that is pre-Late-2011, let me know. You will need to use a different approach than the above.

If the applications that need updating are Apple applications that came with the computer, try going to the App Store Purchases tab or click on your profile and then go to Purchases to see if there is an option to accept the applications with your Apple ID. If that doesn't work, you can delete the applications and download them with your Apple ID. The applications are free. You may have to sign out of the App Store, restart the computer, and sign back in to download new copies.

Purchase History Review