As far as anti-viruses/virus removals/etc go:

• For Windows & macOS, I would just enable and use the built-in anti-virus protection (Defender on Windows, XProtect on macOS).
• On macOS, I would also enable and use the built-in firewall (Nearly every other OS already comes with a firewall enabled out of the box, no idea why macOS doesn’t enable theirs by default…), as well as Lockdown Mode if you’re able to.
• On Linux, I would use ClamAV & ClamTK.
• On Android, I would use Hypatia & Auditor.

I would also strongly recommend making use of DNS level protection through a service like NextDNS, ensuring you have a good content blocker like uBlock Origin in your browser, and using Safe Browsing in your browser (As long as you use a good browser like Brave or Firefox, then Safe Browsing won’t endanger your privacy, it just improves your security and protection, so I’d recommend using it).

As far as encryption goes, I would recommend just using whatever is built-in to your OS, such as BitLocker on Windows, FileVault on macOS, & LUKS on Linux. You can also use VeraCrypt if you wish to as well, may be preferable in some cases, though I personally don’t bother.