Metals with free electrons in their valance shells are commonly used to make wires.
Inside a wire, the charge is carried in the form of electrons.
An electric current is a passage of charges or electrons through a conductor.
The flow of charges inside a wire:
The electric current flows through the wire due to the potential difference between the two ends.
An electric field is formed in a wire when a potential difference is applied across it.
This electric field causes the free electron to migrate in the opposite direction of the electric field (since electrons have a negative charge, they move in the opposite direction) at a rate known as drift speed.
As the field changes from high to low potential, free electrons in the wire travel to a higher potential. As a result, current flows from a higher potential to a lower potential (opposite to electron flow), because electron flow is current flow in the opposite direction.