In my opinion, look for courses that focus on networking and social skills. Vanessa van Edwards has a great course, also Keith Ferrazzi -- I think you can find both of them here on TF. Foundr also have some free courses on networking, but I haven't tried them.
I don't think you need any courses in order to start. Look for friends/family who need help, if they don't, maybe they know someone who does.
If you are like me and you don't have reliable connections, go on meetup and attend some events related to what you want to do. If you are in a big Polish city, there will be plenty of networking events taking place. Attend everything that catches your fancy, especially the entrepreneurial events as these people usually need web developers. Don't start pitching to people right off the bat, just make friends and have fun.
Now, if you are like me and you live in the middle of nowhere, you have a few options -- write online or attend virtual events/workshops. I got my first client by signing up for a course -- I participated in the discussion and a business owner noticed me, the rest is history.
Years ago, I knew a guy who was starting a business and he hired a 20-year old bartender with questionable experience just because she was cute.
Anyway, you can do this without courses. Good luck.