When a capacitor are plugged into the battery, what happens to the Q(charge), potential difference, and C(do all of them increase?). would it have the same effect if two capacitors connected in parallel plugged into the battery

Answer 1

The potential difference of the battery is V, a constant. When a capacitor is wired across it, it acquires a charge Q equal to C*V, where C is the capacitance. C is also a constant.

Connecting two or more capacitors in parallel increases the total stored charge, since they all get added.