Windows defender is all you need. I keep the free version of malwarebytes on my pc just in case something seems off. It does not start up or run in the background tho.
Supplement it with a strong ad blocker and you've eliminated most routes other than phishing for getting malware on your system. It really is shockingly good.
Ditto. Maybe a CCleaner once in a while. That’s about it. You kind of have to go out of your way to get windows infected with something, or just be really stupid like plugging in a usb drive you found on the restaurant floor on your lunch break.