There are a variety of different dishes and cuisines in Germany. In other countries, German cuisine is often associated with pork. Lots of types of sausage are indeed made of pork and pork is roasted. But there are lots of other dishes cooked with beef or chicken or without meat (vegetarian). Turkish and Arab restaurants in particular offer halal food.
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Some sweets, desserts and cakes are made with gelatine, which is made of pork and beef. You can see if a product contains gelatine or other animal products by looking at the list of ingredients on the back. You can also ask the salespeople.
You can tell public institutions such as nurseries ("Kindergarten") or hospitals if you don’t eat pork and they will take this into account. The same applies if you are allergic to some substances found in food (e.g. gluten or lactose) or have diabetes. If you make it known in time, you will be given a different type of food.