
Several short walks is better than one long one, because as a small pup he won't be needing them for exercise, more for training and socialisation. The usual rule is for walks of roughly 5 minutes for every month of his age - so at 3 months he can have 2 or 3 15-minute walks, and when he is up to 4 months they can be about 20 minutes each. The point is not to get him physically overtired.
You say he's a really confident and inquisitive dog. You may be surprised when he is in a strange environment - be prepared!
Good luck with him - I bet he's lovely!