Well done. 'Provided' is the right answer, meaning 'only if' or 'on the condition that'. The word 'Providing' can also be used in the same way. This is a first conditional sentence talking about future time. Note that the first part of the sentence is in the present tense - gets.

Provided.

Of course I agree that 'provided' is the obvious answer; gramatically, 'unless' would be OK too, if the 'permission' is for something other than the skiing, or if the speaker only likes doing forbidden things!

I believe "as" is the answer

i think "provided" is correct