It depends on the horse. As long as the horse has been cleared by a vet to do it and the horse enjoys it then yes. Lots of people do more than one event with the same horse😊
Yes I do it I think that it is great if your horse loves it too
Yes, eventers do both and then some. At some higher level you may need to pick a discipline, but for now you can compete doing both. Also, doing dressage with a jumper or jumping with a dressage horse are great cross training exercises. Have fun!
yes. not the high levels probably, but yes otherwise