A1 Driving licence QUESTIONS

Good day together, my son will be in March 16 and wants to make an A1 license, I would have to ask: how long does this license last? how many driving theory lessons do you need? which mopets giebts in this class? is it advisable to make a driving license for a motorcycle in winter? should he rather only start later or in februar or märz first? says even more what you know about this machine he supposedly wants to have, what do you know about it??