In the first game:
6...Be7
9...Bc8??, your knight is attacked twice and defended twice. You could have simply castled. If you were worried about him removing a defender with Bxf6, that fails because Nxf6 and your knight moves away from the attack.
Second Game:
6. h3, although not forced it wasn't a blunder.
8. c4 is a great move if 8...cxd5 is a forced response. However black can put your center to question and introduce complications with 8...f5.
11. Ng5+ and Nxe5+ are pretty equal. Kg6 is not a good alternative for black since 12. g4 Bxg4 13. Qxg4 fxg5 14. h4! h5 (trying to put the queen to test) 15. Qe6+ Nf6 (if Kh7 then hxg5) 16. hxg5 and you gain much more material. If black tries 12...fxg5 then 13. gxh5+ Kf7 (other options lead to mate, Kf6?? Qf3 and Kh6 Bxg6 Kxg6 Rh1 Kf6 and you have the same position pretty much after the Kf6 variation.
18. Bd7??; as you noted just drops a piece.
21...Rxc5!; if 22. e6 then Ne5, if 22. exd6 then Nc8. In either case your passed pawns are stopped.
I just played two games in live chess against the same opponent, lost one and won the other. Any help analyzing would be much appreciated. I've annotated the games a bit for your convenience.