Question

What is anti- particle ? And what is its relation with black hole or some outer space things like that.

Answer 1

See below.

Explanation:

Simply put, an antiparticle is a particle that has opposite physical charges compared to its particle counterpart. For example, a positron is the antiparticle of an electron and an antiproton is the antiparticle of a proton. The positron has an electric charge of +1 whereas the electron has an electric charge of -1. Similarly, a proton has an electric charge of +1 whereas an antiproton has an electric charge of -1.

The connection to black holes is Hawking radiation. Essentially, a particle and an antiparticle can be created from energy and if those particles happen to be created at the event horizon of a black hole one of them may get sucked into the black hole and the other particle may escape. This means that a particle ends up leaving the black hole, decreasing its overall mass.

Further reading:
https://en.wikipedia.org/wiki/Antiparticle
https://en.wikipedia.org/wiki/Hawking_radiation#Overview