Thank yo for the screenshots, I do not see any Realtek process listed in there.
Open File Explorer, then go to tis folder:
C:\Users\Fangirl\AppData\Roaming\Realtek\Realtek
In that folder is there a file named RealtekUpdate.vbs?
if there is, right click that file and select Open With - Notepad
Delete the contents of that file and then paste this into that file:
Wscript.Quit
Save that file and restart your PC and the popup error should be gone.