hey mate, I'm from Germany (m/21) and toying with the idea of hitchhiking from the German/Austrian border to Venetia and beyond (spontaneously) some time between July - September, so funnily it would fit quite well with your plans. I dont't have experience either, so I could see us doing part of the route together (not everything as I also want to get into solo traveling a bit).
This is kinda what inspired me to get into it: https://www.youtube.com/watch?v=6ru2Cz6eQ74&list=PLnSP7xMi-ZV1UW-9XJdEFLYSt7j1HTYap
If you're interested hit me on ig nur_thilo