can someone explain the first 2 inaccuracy's ?

i dont understand them

9...Be6? is a mistake, as white can open the position with 10 d4.
Black had to play 9...Be7 to prepare 10...O-O to bring his king to safety.

13...Rb8? is a mistake, because of 14 Qa4+ winning pawn a7. Black had to castle 13...O-O to bring his king to safety.

@tpr said ^

9...Be6? is a mistake, as white can open the position with 10 d4.
Black had to play 9...Be7 to prepare 10...O-O to bring his king to safety.

13...Rb8? is a mistake, because of 14 Qa4+ winning pawn a7. Black had to castle 13...O-O to bring his king to safety.

if i castled i would also loose a pawn

Yes, but 13...O-O 14 Bxb7 Rb8 15 Bg2 c4 gives you compensation: all black pieces are active and white has a backward pawn on d2 and a hole on d3.