I've heard from people who tried charging their Mach E with tesla superchargers that It's not a good idea. First, there are only a few tesla superchargers that support non-tesla. If you somehow find one and connect your Mach E physically to the charging station, it will not charge your vehicle, as the charging protocols and software used by Tesla and Ford are different.
Charging a Mach E from a Tesla Supercharger could potentially cause damage to the vehicle's battery or charging system and is not recommended.
To charge a Mach E, you must use a charging station compatible with the vehicle's charging port, such as a CCS (Combined Charging System) charger. Ford also provides its network of charging stations. So, I'd recommend you use a compatible charging point.
I use Plugshare to locate Mach-e compatible charging stations in my area, and you can also find one through this app (It's like google map but specifically for charging stations): Ford Mustang Mach-E Charging Station Map | PlugShare