Hi there! I hope you are well. My name is, Zadee. I'll try my best to help you today.
If you are still able to boot Windows properly and access Settings, I suggest using that Reset method. Otherwise, you can use the bootable USB Windows Reinstallation method.
"Want to know if all-in-ones have Ram memory that can be expanded?"
That's going to depend on how much RAM the motherboard supports. If you want that checked, please see the device manufacturer's manual, you can download that on their site.
Best Regards.