My first drafts were total garbage until a guy at the library showed me his own trash
Honestly, I always wrote one draft and figured that was it, just fix a few commas and hit publish. Six weeks ago I went to a free writing group at the Sunset library branch on Irving and this older guy passed around his own first page, and it was a mess. Crossed out words, arrows pointing everywhere, two whole lines scribbled out with a note that said this part is boring. I asked him why he would share that, and he said his real draft always looks like a crime scene and that is the whole point. I went home and tried it, just letting myself write dumb stuff with no fixing, and my second pass on a 900 word piece took me 20 minutes and came out way better than anything I used to grind on for two hours. The thing is I used to stare at one blank line and freeze, but now I just barf it all out first and clean it after, and it is honestly kind of fun. If you are stuck, what is the worst sentence you have written this week, because I bet it is fixable.
Calling it a second pass kind of undersells what you're doing, because what you're describing is two different jobs. First draft is just getting words on the page, then editing is a whole separate skill where you cut and move stuff around. Once you stop trying to do both at the same time, the freezing goes away, and that old guy at the library knew exactly what he was doing when he shared his messy page.