i created a simple app that generated a pdf with 2 pages now i need to share the pdf and also save it in the device from what i already know it requires permissions to do that.

i am new to this and dont know what to do so i watched some tutorials and read some google articles and found out that the permission stuff and storage access is change multiple times through out android 9-13 my targeted sdk versions are 29-34.

how can i manage all the changes and ask for permissions?
also i cant find any permission that says for non media files. so do i even need permission or not?