Welcome to the community I was in your situation a few years ago when I started learning Unreal. I’ve seen groups like these form a few times, but it always starts with one person working on a project and posting updates here on the forums. Eventually the project gathers more interest and others are willing to join the team. Its a lot easier to get people on board once you show that you have a working prototype.
So my advice would be to continue learning Unreal and start working on your game :). I would suggest going to https://www.unrealengine.com/en-US/onlinelearning and taking a few courses (they are excellent). Also, I would highly suggest buying a beginner course in Udemy (they can be bought for as little as $9.99) and learning from a structured course. This will save you a lot of time compared to watching tutorials on YT.
Then start posting devlogs to get feedback / opinions. Post them here, but also try Reddit and Discord (both are more active than the forums). Also, check out the Community section of the forums for lots of community assets you can use for free (and learn from).
Its a long, but very fun journey
Feel free to reach out if you have any questions and I’ll try to point you in the right direction