I did lots of CTR rides in Region III
It's lots of fun, You will learn a lot and have fun.
Ride in the Novice class at first.
Tell others you are new and most ride managers will assign you a mentor to help and answer questions.
Your horse should be in shape to cover 20-25 miles in 8 hours.
You don't have to ride him every day. But a good 15-20 mile on saturday and something shorter mid week will help get him in shape.
Make sure you can lounge your horse in a circle, right and left
You will need to present him to the judges/vet several times during the weekend on the lounge line.
Teach your horse to stand still while you mount
Each ride is different. But all horses have to be stalled/tied the same. You may have to tye your horse to the trailer over night if the ride you attend doesn't have enough stalls to go around to everbody. Make sure your horse will stay tied to the trailer.
Be prepared to feed & water your horse while tied to the trailer or highline. Buckets, haynets etc.
Have fun