You usually don't need a virus program with Linux. Technically it may be possible for a virus to attack linux but they are extremely rare so far. Virus programs can be installed, but my understanding is they would mostly look for windows viruses.
Most Linux distro's like Ubuntu or Mint come with a basic firewall. Deep under the hood there's a lot of adjustments and settings to lock things down (or mess things up). I have found no need.
Sometimes a slow acting computer is windows going bad. Sometimes it's a slow mechanical hard drive. Linux will act better than windows but the real problem is it needs a new hard drive.
Replacing a desktop hard drive is pretty easy. Laptops vary but are often a pain to change hard drives.
Last edited by gwrench; 01/21/22.
