To answer your question about when to start competing with your horse, it depends on a few factors:
* Your horse's age and training: Most horses are ready to start competing around the age of 4-5, but some breeds and individuals might be ready earlier or later. It's important to have a solid foundation of training before jumping into competitions.
* Your skill level: You'll want to be confident in your riding abilities and have a good understanding of the rules and procedures for the type of competition you're interested in.
* Your horse's temperament: Some horses are naturally more competitive and enjoy the excitement of competition. Others may be more laid back and need a little more time and training to feel comfortable in a competition environment.
It's always a good idea to start with lower-level competitions and work your way up as you and your horse gain experience. A good trainer can help you assess when you and your horse are ready for competition and guide you through the process.
Good luck with your riding and competitions!