Please tell me about void main(void)

Question

how can I use it in c language

Answer 1

void main(void) tells that there is a main() function declaration that do not return any value as it follows void keyword and void inside parenthesis () shows that main function not require any parameter or argument.
It may also be written as
void main()

Answer 2

void main(void)
is same as
void main() used for calling main function