Just write the damn first draft first
It doesn't have to be pretty, don't do line edits and futz with words
You can write inline notes to yourself like [FILL IN LATER] or [LOOK UP PROPER NAME] and then handle them in your editing pass
The art of the first draft is all about establishing a flow state with minimal friction and zero multi-tasking or distractions, just getting the rough sense pouring out of you. Once you've gotten the rough sense of things down, then futzing becomes very easy
Also editing (the watcher at the gates of the mind, the censor, the curator) is a totally different part of your brain/way of thinking than writing (generating, creative, unbridled and unrestrained) so alternating between them every sentence is BAD and inefficient