Doing gives you quick feedback. For example, if I want to get fit, I can sit and think things through for weeks. I can come up with the perfect exercise program, diet plan, supplements list, and ultimately do a whole lot of nothing. And then when I put that plan to action, I may find out that it's too much too soon, that I can't recover fast enough to stick to the program, that the supplements I already purchased make me bloat and give me cramps.

Or I can create a rough plan, start slow and cautiously, and make the necessary adjustments according to the feedback my body gives me. Maybe I start with two days a week, instead of a five day program. Maybe I start with one supplement, like protein powder, instead of the whole stack that includes creating, pre-workouts, post-workouts, sleep aids, etc.

Execution of some venture requires both thinking and doing. But your thinking goes a longer ways when paired with doing. I read somewhere that the sweet spot is 20% thinking and planning, and 80% execution and doing. That's likely not a scientific quantification, but it gets the idea across.

So, yes, in your case, you have a rough idea of what you want, that's great. But don't get lost planning details about which you know nothing about. Make a decision based on a decent amount of research, execute that decision to the best of your ability, and then make an adjustment as you learn more about the paths to your end goal.