If you are not already using tails, you should. If you are using windows, don't even ask (Am I fucked? Yes. Yes you are fucked.)
Refrain from using any computer newer than 2003-2004. Use some obsolete shit for your illegal needs.
The global CIA and NSA mass espionage started in response of the 2001 attacks on the world trade center. Any computer made before 2003 is less likely to contain CIA shit such as learning viruses that stay on a hidden memory in your hard drive and re-upload themselves despite a full system wipe/format, or similar shit.
The same goes for your phone or any other electronic device. Even devices that do not typically feature "intelligence" such as USB keys can be infected.
The CIA does not give a single fuck about some 19 year old kid buying a half sheet of acid. Anyone that is scared of the CIA (in the context of opsec) is grossly overstating their importance.
It really blows my mind that someone thought this post up and actually went through with submitting it. I will never understand how people are so deluded on what the CIA actually does.