Your play in the opening seemed OK--with the exception of 8.b4 (8.d4 was quite a bit better), but I don't understand your comment  after move 8 that you don't know how to exploit Black's exposed king. I can't see that the black King is particularly exposed. It hasn't castled yet, but there are no open lines leading to the King, and White's pieces aren't developed and ready to attack. This is not the time to worry about a direct attack on the King! Your 9.d4 looks perfectly fine, although I would also consider 9.a4. Why not put pressure on both the queenside and the center?

And 10.cxd4 is fine! Your two pawns dominate the center and threaten to advance and fork the Black Queen and Bishop. He has no time to go after your b-pawn. I don't understand why you think 12.d5 is good. Can't he just grab your a1 rook? 13.d5! is the winning move you missed!

17.d5! was also crushing, although you're certainly doing fine after 17.Rfb1. 21.Qf5?? was a catastrophic mistake.; He could have simply played 21..Nxf5 and you are missing a Queen! You were extremely lucky there. But 22.Nxf7 was almost as bad. You seem to have lost the thread of the game here, and you're just not seeing simple captures. Were you running short of time?

Yes. At the end I was running quite short on time. But 9. a4 I had written in my notes as a potential move that I could of used instead. 

And you are right 13. d5 I overlooked that. Overthought. I think just timid to push the pawn. But absolutely no reason not to.

Looking again 13. Bb2?? Clearly not the correct move. 

As for the king just because it seems like he is hanging out there for the potential of a pin doesn't mean it can be exploited? The board has to call for it right?

Thanks looking at my game.

Still learning more about using pawns.