Bucking

My horse is green and bucks Everytime I ride him for at least 5 minutes. How do I stop this?

Make sure his tack is fitting him well. How green is green?

Find a trainer who deals with green horses.

Bubba , I have finished many horses. Yes. Tack fits fine and like 1 month under saddle (we are still only walk/trot)

Do you slow him down or stop when he bucks ? Does he buck at anything in particular, like leg pressure ?

There are many health issues which start off with bucking, have you checked the horse with a vet?

No just when I get on him.

First, you have to be sure he has no injuries. Maybe he has just a back problem.
If not, the best thing to do is to contact a profesional, he will explain to you how to deal with this behavior.
If your horse knows what is the stop-rein, you can do it when he is bucking, and he will have to stop.

this..

Finishing isn't the same as starting.

If your horse is already bucking, I would suggest finding a trainer for you and the horse, you'll learn a lot, and the next green horse will be easier. But why would you put yourself in danger, and damage a young horse's reputation when you yourself aren't educated?

I see so many people 'shocked' when my 6yo late starter is better behaved than their 10yo+ horses. There is no magic in it, its just good training with a good trainer.

Get a trainer, get some help, and then go from there. If its only for the first five minutes there is something that will be either causing him pain, lack of respect for you, or holes in his education- sort it before you end up in hospital.