I think your composition is pretty good and I like your location choices, he seems pretty relaxed so must have felt comfortable around you which is sometimes not as easy as it sounds.
As Nostrum says they could all use some PP especially in the sharpening department. #2 is a little underexposed although it's salvagable (I have done a VERY
quick edit below that would need some noise reduction I don't have time to do any selective masks right now as I am off on a shoot in 10 mins).
Overall though fine effort for your first attempt IMO.