To feed a horse, hold a valid food item and press use on the horse. Feeding invalid food causes the player to mount the horse. Horses can be fed only when.
To grow the pumpkins, you will need to till the land. Using any type of hoe will do the trick. A higher quality material does not increase your crop yields.
The basic Map (zoom level 0) has a size of 128 x 128 Blocks. The zoom level 1 Map has a size of 256 x 256 Blocks. The zoom level 2 Map has a size of 512 x 512.