Or you could just use a thumb drive version of your favorite distro to go on line. Another option would be to use a drive caddie mounted drive to go online, as I do. That drive has no personal info on it. Let them do what they want. I will flush it with the rest of the garbage!
But be careful if your thumb drive or drive caddie distro automatically mounts your other drives. Many distros will do that, and that would put those more important drives and their data at risk too. As
@KGIII said in post #3 above, air-gapped backups of your important data is just about the best protection you can have... after the fact... if you become a victim.
How to keep from becoming a victim takes serious attention. What tools to use, what websites you surf, what software you choose to install, and many other choices that boil down to your own behavior every day. We are all different in that respect, some more cautious than others. As
@JasKinasis said, "It's never going to be zero risk."
I don't look at ransomware much different from any other catastrophe as a home user (corporate networks are a different story). What if your hard drive dies suddenly? What if your whole computer gets smoked by a lightning strike? What if your computer is stolen? Would any of these events be totally devastating for you because of data loss? Again, that air-gapped backup is a cheap and effective insurance policy... but you have to keep it up to date for the best protection.
[EDIT]
Want even more insurance? Keep a backup outside your home... either in the cloud, or on storage media left with trustworthy friend or family. This protects your important data from theft, fire, flood, tornado, hurricane, earthquake... well, you get the idea. Don't really trust the cloud or friend/family? Encrypt the backup first. Offsite storage is the best air-gap you can get.