

A car battery doesn’t have enough voltage to even tickle you* so you wouldn’t even know if you zapped yourself. (*assuming you are touching it with y’know your skin and not your tongue or something even sillier)
Buuuuut if you touched any bare metal bits of the car while touching the positive terminal, for example when fastening the bolt on the positive terminal with an uninsulated tool, then you did just zap yourself for however little that matters with a 12v battery. ;)
were coming for your giggles next