Question

one of your classmates talks very loudly and does not let others participate in class discussion discuss what advice would you gave him

Answer 1

I would like to tell him that  we all are studying together everyone has a right to give a answer if u only answer or discuss always others will not get an opprtunity to give answer so you should stop doing it

Answer 2

First try to tell him in a pleasing way, to calm down. Even he doesn't, give him a sharp and annoyed look whenever he talks loud and doesn't give others a chance.
If this doesn't work, make him realize how annoying it would be when others dominate in a class.
Final option : Go to your teacher and tell her about this. She will definitely help you.