The DAAD provides an overview of international courses. Attention: Even for international courses, institutions frequently require students to demonstrate a certain level of proficiency in German when admitted or after a certain period of study. Read the information from the institutions very carefully.
No, many institutions have an individual profile based on particular research interests, subject combinations or close co-operation with certain other institutions and organisations. This means that studying a subject can be quite different at different institutions. A particular subject name can even be used for totally different subject content at different types of institution (for example, communication studies from a humanities or sociological perspective at a university or as a technically-based engineering course at a technical university or a university of applied sciences).
Courses at a university of applied sciences normally have a stronger practical focus, while courses at a university place a greater emphasis on research.
Choosing the "right" institution is therefore extremely important. Make sure you find out all you can about the institutions (the best way is to visit the central student advice service at the institution of your choice) and then decide which emphasis is the most suitable for you.