Current vs Voltage

Wondering what is the relation between current and voltage?

It's the relation between cause and effect. Voltage causes Current to flow. Voltage is the cause and Current is the effect.

In other words, Voltage is the amount of energy required to move or flow electrons between two points. The rate at which the electrons flow is Current (I) and measured in Amps aka Ampere or Amperage (A). Voltage as well the unit of charge aka Volts required to flow the electrons are both denoted by V.