Assuming he is really into skateboards, I would recommend letting him pick it out.
When I was 12 or 13 my mom tried to be nice and bought me what looked to her to be a modern skateboard (mid 80's) from the local sporting good store. I convinced her to take me to the real skate shop and got a P&P Lance Mountain with bones wheels & tracker trucks....much better :-)
I still buy boards every few years even though I am in my 40s. I like having them around
I would wonder what he wants...even if he isnt into tricks, he may still want a trick board, or perhaps a long board just to cruise.....and with long boards, you have to realize that some are concave, some are flat. Some have camber, some dont. Some are really flexy, some are very stiff. Some are wood, some are fiberglass. Some have kick tales, some dont......the choices are very numerous
Dont buy wheels that are too soft. I wouldnt go below 80A durometer. Really soft wheels might feel nice but they tear up very quickly. In fact the first time he rides it and scrapes a curb or hits a stone, large chunks will be missing and he will be bummed and you will be buying new wheels....I usually buy 80A or 84A
There are some great on-line shops where you pick the board, the trucks, the wheels, bearings etc...and it ships complete with grip tape installed, or, you can buy one already pre-built without thinking about putting all the choices together
here are two i have ordered from quite a bit and highly recommend
https://www.muirskate.com/
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