For almost all schools after high school, you are going to get work experience via an internship. You can often earn some money during the internship. It depends on how productive you already are from day one. If you only join to learn, then you are still a student and it is not valuable for the company to give you a salary already. But if you are already productive and they need you badly, then they will take you seriously and you will also get paid seriously during your internship. You need to apply for an internship in the same way as you apply for a normal paid job. Sometimes the school helps you to find a company to get the internship at. There is a chance that you will be hired by the company after your internship. The school that you need this vocational training for, guides you during the internship.