if you must do things online that are best kept detached from your IRL/govt identity, setup a box running something like Tails that doesn’t accept any non-Tor traffic, and interact with it through a text-only interface (i.e. a shell, or links-like keyboard-driven web browser).
people sometimes discourage using obscure setups because they allow better fingerprinting but that’s not always as bad as it’s made out to be. primarily you want to break the link between your pseudonymous identity and your IRL identity. it doesn’t matter how fingerprintable your pseudonym is so long as the overlap between it and your IRL identity is small. and that’s the reason to prefer simpler interfaces like text-only: they prevent leaking things like cursor movements which might otherwise build a tie between those identities.