So, you don't have the pony yet?
What is the reason for getting a pony? Driving...a pet? Have you ever had a horse of any kind?
Horse ownership has many rewards...and a trail a mile wide of potential problems for the novice owner. Hopefully you have friends and/or experienced horse people who can help. You need to learn about feed, shelter, vet and farrier care just for starters.
I would also not consider a donkey until you have had a horse for some time and gained experience.
And you will learn a lot by hanging around this forum. Lots of people with knowledge and horse-smarts . : )
Good luck to you.
If you ever find yourself in a fair fight, it's because your tactics suck. ~ Marine 1SGT J. Reifinger