Okay kiddo, so a bow is a long stick with a string attached to each end. When we want to shoot an arrow, we have to pull back on one of the strings to make the other one stretch and create tension. This is called the "bow draw".
When we pull back on the string, we use our arm and hand muscles to make it go farther and farther back until we reach a comfortable position for aiming and shooting. This is called the "draw length".
Now, the amount of force required to pull back the bow string increases the farther we pull it back. This is called the "draw weight". A little bow might have a draw weight of 10 pounds, but a big, strong bow could have a draw weight of 50 or even 100 pounds!
When we let go of the string, it springs back to its original position and sends the arrow flying forward. That's how we use the bow draw to shoot an arrow. Cool, huh?