Hi!  I just bought the most beautiful horse, but I know nothing about them!  I'm a bit worried that I bit off more than I can chew!
Oh my yes, they are a huge commitment. They have evolved over the lats 45-55 million years!
Wow!  Well, the farmer who sold it to me did give me some hay to feed it - is there anything else it might like to eat?
There is special horse feed you would need to buy, but hay is good for them to snack on. Horses also can sleep standing up and lying down! 
Holy cow!  That's funny!  I suppose it's going to need its nails done. Or hooves, or whatever!
Yes that can be done by personnel at the barn where you would be keeping him/her or if you own your own land you will need a shelter for the horse and to clean its hooves yourself.
Myself?  Oh oh. I'm not sure I can handle that!  What about keeping him clean and nice looking - he probably needs to be brushed, right?
of course, just like when you get a dog or puppy, it can live fine without being brused or bathed as if it lived in the wild but it is very helpful to bathe and brush the horse for his own comfort.