Pinto is a color and not an actual breed of horse. Many horses are started under saddle at 2-3 years old and not considered fully trained until they are around 6 years old.
It depends... if you don't own your own horse than at my barn you need to be at least 7 years old, but if you own your own horse than it doesn't matter...hope this helped!
It depends on the horse. If I were starting a Quarter Horse from a young age, I would work from the ground until the horse was at least three years old, maybe four.
We start light riding on our horses at the age of two, you do not want to push them too hard until the plates in their legs have finished forming to prevent future injuries.