Question

what makes the energy to get converted in to matter.

Answer 1

I think it would be the concept of Big bang.

Answer 2

This is the difference between the A bomb and the H bomb. The A bomb converts matter to energy and is called fission, the H bomb uses fusion, the uniting of two heavy hydrogen atoms into helium and releasing even more energy. There's also many simpler conversion in chemistry

Answer 3

Ultimately the answer to you question requires knowledge of particle physics