More advice: think in terms of iterations. You might be thinking of everything in terms of some holy grail platonic ideal of the project, when in fact you will hit a number of road bumps and change your mind along the way that may completely change that.

So start smaller. What's a key piece of functionality that might set a good foundation you can build off of? Building this has the dual benefit of giving you a cognitive "win" while starting to work the "bones" of the project into your muscle memory. You'll have a much clearer idea of what the next step you need to take is to get it to that larger end-goal.