There isn't a woodturning guilde in the US that you have to join, start as an apprentice, become a journeyman, and finally be certified as a master. That may still exist in Europe. The only place that I can see it making any difference is taking a hands on class, such as Craft Supplies' school. If you are a complete beginner, as in never seen a lathe, you would not enjoy an advanced class, the rest of the students may get very frustrated because the instructor spends most of the time helping you. Or if you are reasonably skilled and take a beginner course, you might get bored sick learning what a headstock, tailstock, faceplate turning, and turning between centers is.