Help! My PC Seems to Be Compromised, What Should I Do?

Given your situation, it might be a good idea to disconnect from the internet right away to stop any active communication with malicious servers. Make sure your antivirus software isn't the only defense. Create a bootable USB with a rescue tool like Kaspersky or Bitdefender if you can. You should also backup your important files first, but only the ones you’re absolutely sure are safe, just in case. Then, consider wiping the system clean to start fresh.

It sounds like you might have gotten malware from a sketchy streaming site. They can be risky for your security! Can you explain more about how your cursor is acting? Is it moving completely on its own or just acting up when you try to use it? Also, what do you mean by your PC taking prints? That could help pinpoint the issue better.

From your description, it does seem like something funky is going on with your keyboard. It’s strange that the mouse is perfectly fine. You could try using a different keyboard if you have a spare USB one lying around, just to see if that fixes the shortcut issue.

It's a good call to be cautious. If you suspect a compromise, wiping and reinstalling could save you a lot of trouble in the long run. Did you ever unplug your keyboard to rule out any hardware issues? Sometimes weird keyboard behavior can be a simple fix. Also, you mentioned that pop-up ad—was it persistent? Did you click on it or download anything? That might give us a clue on how this started.