The only truly effective way to avoid internalizing conspiracy theories and pseudoscience is to inoculate yourself against them by learning how to recognize them when you see them, which includes learning their history, their tropes, and their overall characteristics. It also includes learning information literacy and strengthening your critical thinking skills. Trying to avoid encountering them at all does nothing to inoculate you, which leaves you vulnerable to internalizing them from an unexpected source. You cannot give in to lazy/reactionary thinking on this one.
(In case you need it: here are resources.)
I want to emphasize here that you absolutely cannot trust your progressive friends to never fall prey to some kind of BS and pass it on to you. Conspiracy theories and pseudoscience are like viruses; they evolve and adapt to propagate in whatever environment they're in. Antisemitism often masquerades as feminism. Christofascism often masquerades as saving abused children. Anti-Black and anti-Indigenous racism often masquerades as sticking it to the white academics. No matter how progressive you think your friends are, you cannot trust them to do your thinking for you.
