How do I stop fear from blocking my writing?

The fear is telling you the writing matters. If you did not care about getting it right, you would not freeze. So take the fear as a sign you are pointed at something true, not as proof you should stop. Good enough is not the thing to chase on the first pass. The page does not have to be good. It has to be honest. Let the true sentence be clumsy. You can make it better later, but you cannot fix a page that stays blank. Try this today: write the one thing you are most afraid to put down, and write it badly on purpose. Give yourself ten minutes and no reader. The fear shrinks the moment the words exist. You are not writing for the fear. You are writing past it.