Difficult question to answer. All branches have very good training. Some branches do a very good job in some areas, while other branches do very well in others. Unfortunately it would depend on what type of training interests you personally.
Each branch does, in accordance with its role. An Air Force pilot trains for combat, just as an Army infantryman does. They just prepare themselves for different roles.
The best place would be Basic Training (or what most people call "Boot Camp") Depending which branch of the military you're interested in joining would determine which training you would need most.
Its, mostly based on perspective, but the Royal Marines probally have the best track record for both. The best in the U.S. is the USMC.
Air force
Depends on what branch of military your joining, your military occupational specialty, and your resident geographic location.
USMC
Is it required for any branch of the military to have new recruits complete a basic training camp. Most camps are eight to nine weeks in length and are designed to train a future soldier to become both physically and mentally fit.
The US Marines definatley have the best.
That is very debatable, all of our military branches are considered to be the best in the world.
Yes, after you finish your service commitment with one branch, you can join a different branch. But depending on which branch you are from and which branch you are going to determines what training you'll have to do. If you are from the Marines, switching to Army, you would have to take a four week training course called the Warrior Transition Course.
The Coast Guard gets more training hours per man than any other branch of service.
The Department of Defense police are civilians and not subject to movement or deployment orders. Their standards and training are different from the military branch police, and they stand outside the military chain of command.
No you have to be 21 with 3 years of training in army and military branch.