There are certain requirements to get charges to move in a predictable and usable manner.  First, there has to be an electrical potential difference.  If two regions have different amounts of charge then they create areas of different potential energy, and their electrical potentials are different.  If you compare the two areas to each other you can determine the potential difference between the two.

A force on the charge carriers is created by the potential difference between these regions of unbalanced charge.  This force, called the electromotive force (EMF)  is what causes the charges to move between the different potentials.  The regions do not have to be charged positively and negatively.  They could be two positive, or two negative regions as long as they are not the same amount of charge.

The second requirement for current flow is the presence of something to receive the energy given off by the charge carriers as they go between the charged regions.  This is generically called a load.  The load could be a single wire or it could be a device created for a specific purpose.

If the load is a single wire then the wire will receive all of the energy liberated by the moving charges.  The wire has no way of getting rid of the energy so the temperature of the wire will increase.  This is OK if this is an electrical heater, but not OK if it is a wire in the wall of your house.
The load is usually a device created to convert the electrical energy into another form of energy; thermal, mechanical, electromagnetic, etc.  Think of anything which uses electricity - that is a load.

The potential difference pushes the charges from one concentration to the other and the load receives the energy from the charges as they move.  This process happens very quickly and brings the two charge regions to equality.  When this happens, the force is gone and the movement stops.  Before you know the device is on, it’s off.

The potential difference needs to be maintained to keep the force alive.  To do this, some sort of pump is needed to move the charges against the field back to where they started.  This pump is any form of energy which involves exerting forces on charges.  The chemical reaction in the electrolyte of a dry cell, the phtovoltaic reaction of metals to sunlight, the electromotive force on charges in a moving magnetic field are the most common.

The third requirement for current flow is this complete path, called a circuit,  which allows the charge carriers to go from one region of charge, through the load to the other region of charge.

There you have it.  A potential difference to force the charges to move, a load to use the energy liberated, and a complete path for the charges to move through the load and back to the potential source are required for electrical current.