I just use Defender and surf the shit out of the web. Never a problem. Use FF, Chrome and Edge. Sometimes websites will freeze my browser, I just restart it. My fav combination right now is Edge (yes, I'm surprised) using U-block Origin, the pop up blocker that is unequaled - they say Windows forums don't even want it mentioned because it fucking blocks everything seemlessly, including their ads. It's the hottest thing going. Go to their website, it takes about one click to ad it to your browser. No restart. Works on the other browsers as well. Edge is faster than the others.
Note: I don't have Ublock on Chrome and it's the one that freezes. Virtually zero problems on Edge.
Once in a while I run Malwarebytes which IIRC always shows no problems found.
Every week or so I let CCleaner do a health check. It kicks off about 30k trackers. Computer speed picks up. Also a fan of Black Vipers Service Configurations.
A good tip is to keep giant folders off your desktop (put the folder in your C Drive and link it on the desktop.)