Too much security renders a computer practically unusable. I'm no fan of Norton--scanning for viruses which have already nestled onto your harddisk is way too late to be implementing security. That's like closing the door after the burgler has already entered your property.
There are several things you can do to mitigate risk and still use your computer(s).
1. Get a 2d computer which only surfs and does nothing else; no emails, and no private messaging or private photos or contacts or appointments-calendar apps.
2. All the stuff you don't want google/BillGates/the CIA/KGB/Mossad etc. to know about you, put on a second computer, which never surfs but does all the rest of your emailing, messaging, photo-archiving, memoirs, etc.
3. Put a firewall between the above two machines, to prevent them from communicating directly with each other. Both Windows and Mac OS offer on-board firewalls which are user configurable to block any ip address or host. Then transfer data between them as needed only via USB stick which you can scan for suspicious files manually.
4. Make frequent backups, in case one or the other machine gets attacked with malware or ransomware.
5. For people who know what they're doing and have Mac OS, I recommend Little Snitch -- a firewall stops unwanted traffic coming in. Little Snitch stops it going OUT, and that is actually more important. If malware can't contact the mother ship, it can't trigger a ransom-demand or transmit your bank details or passwords to the criminals, so they won't know you exist.
6. Add a Russian keyboard to your list of installed keyboards. You do not actually have to have a Russian keyboard, just make sure your computer has a Russian keyboard in its list of installed
options. The reason is that a lot of ransomeware and password/bank keyboard-sweep trojans are created and propagated by Russian criminal gangs (some of them in the employ of Russian intel services). To prevent them from infecting their own computers, many of them check the installed keyboards on the target computer and, if a match is found, the malware does not attack said target.
7. If your service provider offers firewall protection, use it: let them
deal with the constant nuisance of updating the virus definitions, and make sure your router updates its firmware automatically.
8. Never believe it if you get an email which says you must 'verify' your account details or that your account has been blocked because of bla bla and to unblock it you have click on a link. Just delete it without clicking on any links.