Stock Carb adjustment for whizzer ambassador 2

I am having the same problem with the same bike I just bought. + After riding shorts distances (on high idle to prevent stalling) it will not turn over because the battery is drained and need to recharge it again using a battery charger. I'm not sure if the bike is recharging the battery as it should while running. + can't figure out how to adjust the fender so are not touching the tires. I assume "a" screw is the gas flow and "b" is the air flow. when turning counterclockwise they come out more and I can't figure if that is opening the flow more or closing it. I still like this bike and don't regret buying it but hope to ride on it further than my street without worries of making it back home.

Do you know where the "push start screw" srews into? I fugure I'll be using it away from home to start the bike when the battery is drained.