I hate new update. Non of my app are working ruin my computer.

If you search on the web , you can find the clear installer of previous versions of MacOs . Create a bootable usb and then install the previous OS

I didn't have an external hard drive. This means I cannot get rid of Catalina. Despite 2 !!! calls with Apple Support, they cannot help me to be able to shut down my computer! I have to use the power button to shut it off. Instead, it restarts with an error message after I choose shut down. At the end of the Apple Support calls, it seems like it's working. But it really is still broken when I go to shut down later in the day. One of the support people said I'd have to bring the desktop computer into a store. I don't know what the charge for that would be. I am so mad that I fell for this Catalina scam!! Don't do it!!