Thanks for all the responses. I guess I’m behind the times, but I am surprised that a regular antivirus program is not required for security. This is true even with windows 8?
Do you guys trust things like BitDefender et al enough to do online banking on your computers?
There will be lots of varying opinions on whether or not AV is necessary on Windows these days, but generally it's recommended, and any security audit for a company would have a finding if they weren't running endpoint protection. I run it because I'm not concerned about my activities, but with all of the zero-day exploits, compromised servers (from normally trusted websites), and similar threats, running a good AV program is vital, IMHO. Ideally you'll find an AV program that doesn't solely rely on signatures, but also monitors behavior and suspicious/abnormal activity.
Win8 overall is typically considered less secure than Win10, so I'd recommend AV. As others have pointed out on here, you also want to run a good browser and ad blocker (I'd recommend Chrome/Firefox with uBlock Origin at a minimum; HTTPS Everywhere and DuckDuckGo's extensions are also useful). Also, keep your system and software fully patched.
I have no concerns doing online banking, especially if they offer (and you use) two-factor authentication (Duo, Google Auth, etc.). Bitdefender even has a "banking mode" (I don't remember exactly what it's called), but it's basically an isolated browser session that doesn't allow any other sites or plugins to access; I don't use it, but it's available.
I have no doubt there will be others that post the exact opposite opinion, and they do have valid points about some AV programs being worse that some malware. You've started with this forum and you'll get some good opinions & suggestions, so you're on the right track. From here, you'll need to do your own research and decide what your risk tolerance is and what makes the most sense for you personally. Good luck!