Hi everybody

I'm pretty sure my computer has a virus. I have Windows Defender & have scanned my computer many times, but it never finds anything. There's a program (a weird version of Norton Anti-virus or something along those lines) that always has pop-ups saying that my computer has a virus, but when it tries to take action, it fails. Does anybody know of a good free virus program that could help me out?
"Some stories don't have a clear beginning, middle, and end. Life is about not knowing, having to change, take the moment & making the best of it, without knowing what's going to happen next. Delicious ambiguity."
-Gilda Radner