There isn't a 1-step perfect solution as far as I know. You can use Tor in combination with other technologies, and it'll likely help you avoid a lot of surveillance, just not specifically the NSA. (Also keep in mind anyone/commercial actors can run Tor nodes with the intention of spying on Tor users. You need a lot of nodes to catch anyone, but I wouldn't assume it never happens).

The main thing is to own your software and hardware, and disconnect what you don't own from the internet. If you can't meet those conditions, then it's impossible no matter how vigilant and knowledgable you are.

My recommendations is to play your computer games on an offline computer via GOG purchases, or if you want Steam games, then just give up on securing that device. Have two networks. Have your secure computers for your general online tasks and chatting, and have the unsecure computer for interacting with DRM and services that lose a lot of functionality if the surveillance vectors are blocked.

Bad attempts at hardening often don't work, and have the adverse effect of making you more unique for fingerprinting. It might be worth foregoing some hardening advice if you can think of workarounds the hostile actor might use, which you don't know how to counter-act.