Okay kiddo, so the Household Cavalry Coach Troop is a group of very special soldiers in the United Kingdom. They are part of the Household Cavalry, which is a fancy unit in the army that protects important people like the Queen.
Now, this Coach Troop is extra fancy because they ride these big, beautiful horse carriages that are called coaches. They have to take really good care of the horses and make sure everything looks perfect before they go out on special occasions like parades or ceremonies.
The soldiers in the Coach Troop wear really fancy clothes too, with red tunics and shiny helmets. They even have swords that they carry with them!
So, in short, the Household Cavalry Coach Troop is a group of soldiers that ride horse carriages and dress up really fancy to protect important people in the United Kingdom.