Question

اگر توانایی اش را نداشته باشم به شما خواهم گفت ( هر دو در آینده )

Answer 1

If I am not able to take it through/handle it on my own, I will tell you/let you know.

If I don't find the needed ability in me, I will tell you/confess to you.

Answer 2

I'll let you know, if I don't manage.

Answer 3

If I won't be able I'll tell you

Answer 4

If I find myself unable, I will let you know 

Answer 5

اگر منظور توانایی مالی است afford از همه مناسب تراست.

If i couldn't afford i will tell you.