Well if you can, you should look for a city that has a big club in the upper leagues such as TTBL, 2nd Bundesliga, or below.
The reason for this is that the chances are higher to be able to play everyday. So Düsseldorf would probably be your first address, since they also have the Andro TT-school there, but there are also many other good clubs in other cities.
There are quite a few clubs over here, but some are only open like 2 - 3 times per week.
Also maybe keep in mind that many smaller clubs don:'t have a hall on their own and have to use school or university sportshalls and therefore cannot use the hall as they wish. So another reason for a bigger club that has its own TT-hall.
But there actually is no golden rule to this. A big Club can be much more anonymous and hence also more difficult to find practice partners, whereas in a small club things are more personally and a coach can also take better care of you. So in the end big clubs and small clubs both have their positive and their negative sides. So it also depends on how good you can socialize.
But if you know where you're going to study, we should be able to find you a club that fits your needs.
[Emoji106]