How can i figure out if the gas, on my two stroke engine for my mini bike, is making it to the engine?

Basically, I got the bike after one of my dad's friends wrecked it, but when I pull the pull start it sounds basically like a lawnmower when you haven't primed the engine with gas. It did have an electric start on it, but they also lost the key before giving it to me. Can anyone help me?