YOU SAID:

へたですから、試合（に）出られません。。

INTO JAPANESE

へたですから、試合（に）出られません。。

BACK INTO ENGLISH

Because I'm not good at it, I can't play in the game.

INTO JAPANESE

上手ではないので、ゲームに参加できません。

BACK INTO ENGLISH

I'm not good enough, so I can't participate in the game.

INTO JAPANESE

実力が足りないので、ゲームに参加できません。

BACK INTO ENGLISH

I can't participate in the game because I'm not good enough.

INTO JAPANESE

実力が足りないのでゲームに参加できません。

BACK INTO ENGLISH

I can't participate in the game because I don't have enough skill.

INTO JAPANESE

スキルが足りないのでゲームに参加できません。

BACK INTO ENGLISH

I can't participate in the game because I don't have enough skill.