Intelligence. Be careful where you go to on the internet. Be careful what you open in your mail. Never click a link in an email. I have Windows defender, Windows Firewall and never have a problem. Just say no to porn sites and torrents.
But really, when I did use Windows I wouldn’t use an anti virus, like another user said just don’t click dodgy links. And maybe once a month or once every other month I’d download some program and run a full scan.