Question: I am really confused in the terms **Temperature** and **Thermal Energy**. When I tried to look about it on internet, it mentioned that :  

Temperature is the measure of average kinetic energy while Thermal energy is the measure of total kinetic energy of the body.

I want the explanation for it, like how? If a cup is hot, then why does it depends on the average kinetic energy of the body and not the **total** energy of the body?

Answer: 
Suppose a cold cup of water has internal energy $U$ and a hot cup of water has internal energy $5U$. If you have 5 cups of cold water, you have $5 cups \times U/cup = 5U$ internal energy, but the water is still cold.
The term “thermal energy” is vague and should be avoided. Moreover, stating that thermal energy is the total kinetic energy of a body makes no sense. There is the kinetic energy of the body as a whole (e.g. the kinetic energy of a ball in flight) and the separate kinetic energy of the molecules of the ball, which is a part of its internal (microscopic) energy, and that temperature can be considered a measure of.

I recommend you think in terms of the following:

Internal Energy: The sum of the kinetic and potential energy at the molecular level due to molecular motions (kinetic energy) and intermolecular forces (molecular potential energy).

Mechanical Energy: Kinetic and potential energy (e.g. gravitational potential energy) of an object as a whole due to its motion and position with respect to an external (to the object) frame of reference.

Temperature: In kinetic theory, a measure of the average translational molecular kinetic energy (the translational molecular kinetic energy component of internal energy).

Heat: Energy transfer from one body to another due solely to a temperature difference between them.

Work: Energy transfer from one body to another due to force times displacement.

Hope this helps.