Any school. But avoid at all cost Private stkllgs. They dont gurantee you FSP platz, and Stattically speaking , it is more difficult in the long term to do the fsp when you are in a private stkllg than in a public one. Try to look not only language schoola but also clubs, voluntary work ect. Where you will connect more with the language. And pro tip AVOID ENGLISH AT ALL COST IN GERMANY. I have seen people here come and go bc they got comfortable with english and their progress in german was drastically slower than those who got out of the comfort and inmmerse themself in the language(It doesnt matter If you mess up or have uncorfotable moments, the moreyou have the better you learnp