I just use WIndows defender like most people. I would just stay off dodgy site and don't download software from peer to peer torrent sites etc. These often have viruses in the keygen/crack applications.
Where I work everything is backed up to a server. Last week an outside contractor came in whom supplies printers/copiers etc, had some drivers to put on the server, gave a USB stick to the administrator to install them to the server. There are obviously faults here and hindsight is a great thing, but you've got to learn from it, instead of saying "this should have happened, being in-place" or whatever. The stick had the BOPADOR virus on it, hidden somewhere. This has totally wiped the server, encrypted all the files with a really complex encryption key. A message is left with a ransom demand and an email address, in this case it is 2.3 Bitcoin's, which I believe is getting on for 20 grand, the recipient is thought to be based in Lithuania. I'm sure that these people cannot be trusted, but at the same time the information lost is vast.
I guess what I'm trying to say as I'm no expert, but it goes without saying anything at all of any value on a computer should be backed-up. After dealing with bigger companies that only allow their own personal drives to be used on any of their computers, no outside devices now allowed. I kind of thought that this was some corporate over-the-top carry-on.. I kind of get it now and agree with it.
This is not really applicable to the post, but I kind of thought this kind of thing was a fallacy or something. It also got my thinking if a hacker/malicious software ever got into some huge company or some vital computer system.
But just use Windows defender. I've used other in the past and found them a bit too intrusive, but that was ages ago..