Whenever a problem is scoped way too big, we reduce scope by splitting it up into smaller, more manageable chunks.
Give yourself 4 - 8 hours to make a game, something. It needs to be finished in 8 hours, so go extremely lax with the things you want to implement. The timeline of 4 - 8 hours will force you to stop overthinking about everything and instead shift your attention towards getting things done.
If you struggle to do this, then you need to continue working on this until you are more comfortable being put in a situation where you can cut features rather than trying to be a completionist.
If you are struggling with ideas for your game, make a game where a circle collides with a rectangle and bounces off of it, there's half of pong for you.
