'I could do a lot of things - and I do.'
Dedicated practice means many things. But start with “every day,” “learn from failure,” “fail fast,” “break complicated tasks down into smaller chunks and get good at those smaller chunks.”
A passion is a theory. Now you have to test your theory. The world is your laboratory. Construct the experiment that will test your theory. Then test and test and test and tweak and test more.
Some people think they have a passion. They don’t. In 80 years of life you might have 500 passions. 500 things that are your “purpose.” Don’t be hypnotized by any one of them.