what is a form of energy that is always transferred from a warmer substance to a cooler one?

I believe it is "heat".

Are you in 9th grade?

Errata:

heat ENERGY

It's heat energy

The form of energy that is always transferred from a warmer substance to a cooler one is heat. Heat transfer occurs due to the difference in temperature between the two substances. When two substances are in contact, the atoms or molecules in the warmer substance possess higher kinetic energy, causing them to collide with the particles in the cooler substance. These collisions result in the transfer of thermal energy from the warmer substance to the cooler one until the temperatures equalize, leading to a state of thermal equilibrium.