Answer 1

The SL Q&A might not be the best place for these kinds of query, but
if you're using Windows, I find the built-in Windows Defender more than enough to protect your PC. For Linux and others, I doubt there is a need for one. I'm not an expert in this field, so my words do not hold my weight. I personally think we have almost arrived at an age where there is no real need to purchase an antivirus software.