Welcome to the fastai forums.
fastai teaches you how to train ML/DL models with state-of-the-art methods and teaches you this from a practical point of view (you will be training models along the way).
Finding an area you want to apply deep learning is now in your hands. That being said, it will be easier for you to apply what you have learned and create useful models or companies because of the top-down approach of fastai.
A lot of people finish fastai and go on to create successful startups or work for AI companies. I am not sure there is a compiled list of these but you can watch Lesson 0 by Jeremy where he talks about these issues:
I don’t think you can get specific startup advice (maybe I am wrong) but just do the course and train models in your area of interest and you will be halfway there.
Cheers. Good luck on your journey