The upply usually comes from either your outside meter box as @Phaedra says or from the inside meter cupboard. The meter tails that come from your electric meter to your consumer unit are split and a small conumer unit fitted to supply the charger only.
You can come from the household consumer unit but, thats less common and can take up 3-4 ways, making the need for a larger consumer unit or by taking up valuable ways in a smaller consumer unit, that maybe needed in the future.
If your outside meterbox or inside meter cupboard is on an outside wall and is within 10-15m from where you would fit an EV charger in the future, Motability will fit you one for FOC.
