James Allen breaks imposter syndrome into three steps: learn from accomplished people, build expertise by completing projects, then teach what you've learned. You don't need 10,000 hours to be an expert, just enough knowledge to help someone a rung below you.
Number 1, learn from people who've done it well and study your tail off. Number 2, implement everything that you learn. Be the person that completes something. That's what's going to help you build expertise, and it's going to give you confidence that it will— if and when that imposter syndrome rears its ugly head, you have so much social proof to back you up against your imposter syndrome. Well, I've done this, I've studied my tail off, I've implemented everything. I think I'm pretty qualified to teach this. Teach from your own experience. That's number 3. An expert is someone who either has done a lot— they've put in like the 10,000 hours— Or it's someone who's also just very knowledgeable. You don't need to be the most successful. You just need to be one rung higher than someone that you can help.
