I am only able to answer your questions in blue.

Orientation will be mostly talks, information sessions, etc by the University itself, library, and the most important one, by PTPTN. And yes, I think most talks will be at Dewan 2020. Bring extra jacket if you don't wanna get frostbite.

Moving on to your second questions. Not all subjects (like wajib subjects) have labs and tutorials. But ALL core subjects have all these three elements. Don't skip any tutorials, as most lecturers will give "tips" during their tutorials.    Lab is equally very important as well. Some labs will have lab test at the end of the semester. Similarly, do not skip lectures.