What is the meaning of electrode potential? When we say that the electrode potential for $\ce{Co}^2$$^+$/$\ce{Co}$ is -0.28 V and $\ce{Cu}^2$$^+$/$\ce{Cu}$ +0.337 V, what is the physical meaning?

Can you conceptually explain when two electrons react with $\ce{Cu}^2$ or $\ce{Co}^2$to form the metal, what happens and what is the source of these different potentials?
The potential difference between two electrodes represents the voltage that is generated between the two electrodes that will allow the transfer of current/electrons. Physically it's basically a measure of how strongly one electrode attract electrons over the other which leads to the flow of current.