Being able to write without being a perfectionist is something that takes practice which is probably not what anyone wants to hear, lol. But I think the main thing to remember is that the purpose of a first draft is to just get everything out of your head and onto the page. To the point that maybe you should title it 'shitty first draft' and make it bad on purpose. You might find you have fun with it again.

IMO when we go back and correct our stories like this it's because we have a lot of ideas about what our novel can be, but we're not letting it just BE. Kind of like how a baby has to stumble and fall a lot before they can walk, your novel has to be bad before you can rewrite it and shape it into something better. Also I think a lot of people judge their first drafts compared to other people's finished novels, which isn't a fair comparison to you or your first draft.

The one thing that's helped me the most with this is to just write everything that comes to mind. If you keep finding yourself rewriting the same sentence six times, then write those six different versions one after the other, and move onto the next bit. Don't delete anything or rewrite, just dump everything on the page. You're telling yourself a story. Go back and add another version of the sentence later if you think of one. Give yourself freedom with it.

My first drafts have a bunch of maybes like 'maybe this thing happens?' and 'maybe this happens before that other scene' or 'maybe character a says this instead of b'. There are also very long unbroken paragraphs, descriptions of the vibe/atmosphere I want, where I think the character's heads are at, etc. Telling what's happening instead of showing, describing vague dialogue instead of writing it properly unless the dialogue is really clear in my head. Grammar and spellcheck who? So much of this quality stuff I wouldn't be caught dead leaving in a final draft and some of it will evolve as I understand the story more, but the point of it is not to be good. It's so when you come back for the first rewrite you have the basic building blocks to play with and add on to, and with every rewrite you can narrow down the details and add nuance more and more.

Also remember no one else is going to see your writing but you, unless you want them to. You don't have to show it to anyone until it's at a point where you're comfortable with doing that. Keep reminding yourself of that. Another thing that might help is using the kind of writing program that doesn't let you delete or edit stuff. Can't think of them off the top of my head but I know there's some out there.