Why do i always get hot and sweaty from the inside of my body?

It's why you sweat: Sweating is the body's way of cooling off. It is the core body temp. (the inside of your body) that you internal thermostat is regulating. If it is cold then you shiver, if hot you sweat.

Normal: The body generates heat as a normal process. If you feel you sweat more than others, this may be a normal variant or perhaps something else is going on that should be evaluated by a physician. The body sweats to release heat. If you are overweight or have thyroid issues, it may be exacerbating the problem.