Generally speaking, it is open to foreign citizens, but please bring your passport and other documents, especially in a country like Germany, but there is a very important premise that your German is good enough, because the English collection in the German National Library is very limited. Of course, this limited amount is enough for you to study in the sea for about a year. If it is simply to understand their history, I personally suggest going to the museum. Then I don't know. In France, German libraries, like those in China, have a loan period, but now libraries generally don't encourage you to take books out of the library. They will give you an index list, which you can read online (which I sometimes do in China). Books that are very important or exceed a certain period of time are not allowed or only allowed to be borrowed by specific people (such as scholars), so it is the same procedure as applying for a library card in China, and it is also common for the public. Of course, if you need to borrow books very much, it won't be too much trouble to go through such temporary procedures. But you should have enough time and patience. In your question, you want to know the views and values of westerners and some problems in their history. In fact, I personally suggest that you can visit the foreigners around you directly or talk to each other, because it is more intuitive and convenient. Of course, if it rises to the academic field, the library is also a way.