Re anti-virus, a few years ago I discovered my laptop was running both Avast AND Windows Defender and resources had become somewhat precious - I disabled Defender and things sped up quite a lot. More recently I've ditched Avast and use Defender which seems perfectly capable.
However, I do have CCleaner which I run every now and then - a new version uploaded itself earlier this evening, then I noticed that Avast had installed itself - I presume that was an accidental click by me when closing the CCleaner window... Now de-installed...