how do I remove and reinstall other applications such as Zoom and Google Chrome

Zoom is wrought with hacking problems and it is not recommended to install it at the moment. It appears to not have problems with hackers on an iPad, but I would not allow it on any of my Macs. As for Google Chrome, no hacking problems, but it is known as a resource hog - meaning it'll gobble up all the RAM and processor power you've got making it more difficult to use any other app while Chrome is running.

If you uninstalled Zoom, but it is still creating problems, contact the developer for proper uninstall instructions.

Sounds like a real customer oriented business. In their defense, they probably have their hands full trying to get some updates out to ward off the hackers who were able to penetrate while there was a meeting and flashed other content onto everyone's screen.

Put in the Trash and empty the Trash. Download the new apps from the Mac Store or from the developers and follow the install instructions.