A state function used to describe a thermodynamic system with a chosen set of natural variables. Internal energy, enthalpy, Helmholtz free energy, and Gibbs free energy use different variables and serve different environmental constraints.
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Thermodynamic potential is a fundamental concept in thermodynamics and statistical mechanics that represents the potential energy of a system in thermodynamic equilibrium, typically as a function of its state variables. Thermodynamic potentials are used to describe the equilibrium properties of systems, predict spontaneous processes, and derive various thermodynamic relations.
chemistry.stackexchange.com/questions/7696/how-do-i-distinguish-between-internal-energy-and-enthalpy/7700#7700 has a good insight:
To summarize, internal energy and enthalpy are used to estimate the thermodynamic potential of the system. There are other such estimates, like the Gibbs free energy G. Which one you choose is determined by the conditions and how easy it is to determine pressure and volume changes.