Studying abroad by exchange is also studying abroad. Look at your student ID card when you were in Japan and how to define your identity.

I think it can be written as xxx admission first, then xxx specialization ends (or nothing is written after the end), and the staff will tell you how to fill in the blanks. Be sure to prepare all relevant supporting materials. It should be no problem. Don't fill in what you don't understand, or you will have to fill in the whole form again once you want to modify it.