There is no secret. As long as you eat more calories then your body needs, you will have belly fat.
Only by eating less hence putting less calories in your body or by  training hard andu burning more calories .
There is no secret.

I believe our brain is always used. Even when we sleep our brain is in activity.
So the answer would be ALWAYS.

Just typing add url in google should already help you.

Normally around the adolescence years  humans start to develop the need for sex and consequently procreation. Obviously not everyone develops this need so I would say that this is not a bad opinion at all. Just a different one that the mainstream thoughts.

An emotional feeling is not just nothing. There is much more behind this feeling that beats the eye.