Sorry Windows(r) users, but this will not pertain to you. You can find similar advice and information on Windows(r) security websites.
If you use Firefox web browser under one of the many Linux OS distributions, then this article gives good detail about how to set security configurations AND install numerous software addons to "enhance" your security profile.
Disclaimer: I DO NOT use all of these addons. I also do not profess to be an authority on which ones are a better choice. So read the article and make an educated decision.
My advice: DO USE HTTPS Everywhere as a minimum.
NOTE: Javascript is a real vulnerability. It is used in so many places that it is very much like a bacteria which has adapted to the body and made itself indispensable. If I could do so without causing websites to fail, I would turn it off, but that means that many utilities and forms will no longer work. You have to decide on this point.
https://linuxconfig.org/protecting-your-privacy-with-firefox-on-linuxIf you are not comfortable with tweaking your Linux install, then do consult with whoever did your install for you.
Since many of the configuration changes require that you KNOW what you're doing and accept the risks, think carefully and do your research.
It's a nasty virtual world out there and you cannot be too safe. This is part of your Prepper plans, really.