A few days ago I put a trojan by accident on my brother's computer because I'm an idiot. It was because of downloading a pirated game.
The file was detected as Trojan:Win64/Lazy.PGLI!MTB and it was quarantined by Windows Defender, I think.
However, every time I restarted, I got a message saying that a file called "Ome-Relay.exe" was being used by an unspecified program. Then I used Malwarebytes and it blocked a file called ZoneDispa.exe multiple times. That removed that message. However, even though the deep scans say there is nothing in the device, I don't think it's clean at all, because those files that were created in C:\ProgramData are still there, and I don't know if the trojan installed more malware or something.
While I was searching for the Zonedispa.exe file hash in PowerShell, after a while, the screen flickered like when the resolution is changed, the background turned black, and the icons rearranged themselves, and then I saw PowerShell constantly updating in my Windows user account (like C:\Users\"my user">). The black background issue isn't the first time that happened; it also occurred when I was scanning with Windows Defender and Malwarebytes. I don't know what it means.
That was the only thing that really happened, because our accounts are fine since I didn't have wifi at the time (although I'm not sure if I had it on when I installed the virus, probably yes) and I rushed to log out and change passwords from my phone. But even so, since I can't find anything about this virus on the internet, I'm honestly very scared.
The most important thing for me is to save my brother's projects, but I'm not sure if that trojan could have "stuck" in those files (which, by the way, I saved to a new Google Drive account yesterday since I don't have a USB drive handy) I don't know if I should trust antivirus software 100% to scan my saved files, since it has a margin of error.
What am I supposed to do? Those are not important files about money or anything, but are my brother's creative projects and I'd feel awful if they were ruined because of me (I already feel awful). Most are text, image and video files, but there are also godot files and some .rar files and other file extensions. Can I save those files?
What I plan to do is completely reinstall Windows using a USB drive with the help of a friend that's a computer tech, but he is out of town for the time being and I want to know what to do in the meantime. Could someone give me some advice? This situation is literally eating me up inside. Currently the of is turned off, completely from the electricity, because I shitted my pants š