Ok the valve is the whole thing surrounding the piston I understand now How the engine works..but tell me if i got this right..Please its important to me to know this..19 years old and i dont know crap..ok here goes

I dont understand turning the battery but Intake comes in air enters where the piston is combines with the gas and the spark plug ignites a small charge of sorts and the piston contracts down then back up the intake lobe closes then it goe back down then the exhaust Lobe opens and lets out the Exhaust the Exhaust then leaves through the Headers then goes down and out of the Exhaust Pipe??