Why is my new front wheel not spinning?
The most likely problem is that the brakes are rubbing.  If you pick up the front of the bike, hold your head near the brakes and spin the wheel you shouldn't hear any noise from the brakes.  If you do, then the brakes are rubbing and that's the first problem to be fixed.  To be honest, I'd guess that's 99% likely to be your problem.

If you have fenders, and the new tire is larger in size than the old one, then there may not be enough clearance for it; that can also be detected by listening for rubbing sounds.

If the brakes are fine and nothing else is rubbing, pop the wheel off the bike and try spinning the axle; if it doesn't spin freely then that means there's too much pressure on the bearings.  (Note this is really unlikely if the shop only changed the tire.)