Let’s talk about the thing that stands in the way of most novels ever seeing the light of day.
The hardest part of writing, by far, is actually writing. The first draft is thus the hardest bit of the whole process. It can feel impossible when you’re just getting started, and again at regular intervals afterwards. The best way to move forward is to reframe it in your mind. Your objective is simple: get the first draft over with as quickly as possible.
Quality is not a factor.
Your only job is to produce words. Any words, within reason. You should write down whatever comes to mind, and avoid assessing it if you possibly can. Your task is just to produce words. Garbage words are fine. Garbage words are actually better. And don’t even think about editing yet.
Look at it like this: fixing already-written words is about a hundred times easier than writing them in the first place, so you truly don’t need to worry about the words you’re writing in the first draft. Do not fix as you go, because you can easily fix them later. Try not to even proofread as you go. Don’t fret about phrasing and pace and all the rest of it. Just write words.
Your first draft will be, comparatively speaking, crap — when compared to your final draft. Your first draft can’t be compared to anything else, and it definitely can’t be compared to finished books that you’ve read. You don’t have access to the first drafts of The Hobbit, or The Shining, or whatever book you’re implicitly beating yourself over the head with. The comparison is invalid, dishonest, and counterproductive.
Your sole purpose is to write words. They will be the crappiest version of those words, by definition, because you’ve yet to edit. You will fix it all later. The fixing will be easier than the writing, but fixing words requires that you’ve written them first.
Let me offer some hard-earned wisdom. The problem you’re having is that you’re treating the first draft like a final draft, or even like a revised draft. You’re approaching it as if it’s meant to be something you’re proud of, or that you feel is ready for somebody else to look over. That’s not what first drafts are. The goal is actually to write something that is complete, and also crappy and embarrassing. If you’ve done that, then you’re a professional instead of an amateur. Amateurs write a bit then re-read and edit, then write some more, and so on — and it takes forever. Professionals write a whole lot of garbage, finish it, then re-read the whole thing and edit it.
Write a crappy first draft. Embrace the liberation of having no expectations at all with respect to art, quality, or anything else desirable. Write quickly. Write sloppily. Write garbage. Don’t look back.
You will fix it later.
The only way to fail is not to finish.