Prebook Alpine route Japan?

I want to do the alpine route in Japan from east to west from Matsumoto to Tateyama. Should I book the transportation for all its parts? can i get the link to purchase it?

When coming from the direction of Matsumoto, advance reservations can be made only for the first bus from Ogizawa. You cannot book the other means of transport along the way (where it is a first-come first-board system). It is explained further here:
https://www.japan-guide.com/e/e7551.html#section_orientation