You are bound to :
You is "Rest"
You see that I am more than one,
There is multiple type of musical rest (full, half etc...)
Without me you cannot have won.
Without rest, you are not at full potential to compete ? OR can't complete (win) a music going off by one rest will break the melodies
Puzzle out how much I have done.
During rest, we dream. Puzzle out mean "figuring out what the dream mean"
Hiding in measures you'll find me,
A rest can be found in musical sheet
Part of power that helps you see.
Not sure, may referre to a rest in physics. See Newton's firts law of motion
In kids transportation I'll be.
Kids often sleep during long period of transportation
Shapes and words, I am all around.
No matter langage and living races, everyone rest.
At the beginning I'm often found.
First thing you do on your day is waking up (from rest)
Tell me, to what number am I bound?
Rest is bound to 100 (counting 100 sheeps to go to sleep)