My USB ports aren't working after installing MacOS Sonoma

I recently acquired a imac Intel computer through a bidding on abandoned storage unit. Anyways when I got her home cleaned up and turned on It was outdated and not updating with the current MacOS operating system. I ended up using an external hard drive to update it to the Sonoma version. Everything was great and then it had an update through apple's automatic software updates.

Now my USB ports just stopped working, and now I can't do anything after I turn it on. I can't type anything. I can't click on anything to get into it. I did read somewhere online that the newer Mac computers don't have USB ports in favor of Bluetooth and wireless connections, so that could have something to do with it, but I need those to revert back to the older macOS version just so I can get all my programs and pictures off of it and figure out how to go from there as far as updating it goes.

Any information you can provide would be great. I'm not super tech-savvy when it comes to Apple products, so please baby steps with me.