It's Not Illegal to Ride a Scooter on Pavement in the UK

It is not illegal to use your scooter on the sidewalk, but you must be considerate of other users. Be aware that drivers of cars and trucks might not consider you to be on a sidewalk.

In the UK it is legal in the UK to rent e-scooters on public roads (except motorways) and in cycle lanes. It's not a legal requirement