The cd command (in Windows 7 at least) in cmd without /d switch doesn't allow you to change drives. It only changes to a directory on the current drive. Bui that might be different in Windows 10.

My LG G4 (with Android 5.0) needs to be set to MTP before it gets a drive letter in Windows Explorer (fully automatic). No need to install WebDAV.

Can you access the folders on the tablet from File Explorer? If so, I would limit playing with cmd to normal Windows discs, diskettes, USB-sticks and optical disks, unless your course is about networking Windows and Android.