Go prove your doubts wrong.

Speaking of your aspirations, if you want to pursue something, then pursue it. Get to work immediately. Put it into action. Not more thoughts. Actions.

If you're going to do it, then do it with full force.

Do not delay your effort.
Are you doing it now or not?

Do not distract yourself.
Are you doing it enough or not?

Do not defend your avoidance.
Are you capable or not?

You can doubt. There's always some doubt, even if it's the tiniest sliver. But doubt can't stop you from doing the work. So, if you doubt, take action while you doubt.

Go prove your own doubts wrong.

Brick by brick. Do the work.