since you are very familier user with 2D then you will not have difficulties learning and changing to 3D
The new method in CAD is to design 3D then generate the 2D drawings.
Youtube have plenty of very useful tutorials you can learn by doing and following the tutorials.
The help is useful but it is taking indivisual commands, the better is to get a book and learn from there.
Also good people like the available here will support you.
good luck