Not an expert (me).

Over the years I've been attacked a couple of times by the type of software that threatens to expose your internet wanderings and threatens to lock up your system. I haven't conquered them but since I set up several accounts when I bought the computer I've been able to log in to a spare account and save anything I really needed to from data files.

Otherwise I use free versions of Malwarebytes and AVG free. They want to sell you on their other benefits and abilities to fix your system, especially AVG.

I would like to learn more about viruses and detecting them, for now I haven't seen a good primer or educational text on the subject.

Just my .02 bitcoins...