2 stroke 80cc motor

Hey guys, need some help here. Just a got a new bike and I mainly bought it because I loved the rims on the bike. The rims have 140 spokes and I really didn't think about how to install the rear sprocket before I bought it. Anyways, I have a pic of what it looks like below, but my main question...

Okay so I have a G series 2 stroke 80cc motor, when I go to try and stop cause as of right this minute I don't have brakes so, what I do is let go of the throttle all the way and I'll push the clutch in, but when I go to push the clutch in all the way, the engine revs really high and this is...