Get 3 so if something happens to 1 they still have company. Some goats eat everything such as Bagot and I think Anglo Nubians (haven't had them) including Ragwort (poisonous) - check your pasture by the way and know what are the regular common pest plants. Some are fussy and don't so if you're looking for weed control make sure you get the type that eat everything but watch that pasture!
If they are your first ever goats try and get placid natured ones that aren't climbing the walls.
And get a milking stand / goat crush which will help you handle them for foot trimming which needs to be done once a month (their feet need trimmed much more than sheep) and it would be good for you to see this done before you do it yourself. You can make one yourself - do the search at the top of this website and it will come up with previous entries about this and member's having made them successfully without too much hassle.
They need goat mix or dairy nuts (normally fed to cattle but good for goats) normally about as much as cupped hands together amount each goat twice a day, fresh water and a mineral lick which is suitable for goats.
And remember, goats like to browse more than graze so you have to have access to things you can chop for them - ours especially like ash branches and fruit tree branches. If you don't have access to lots then you could always offer to chop someone's unruly bushes somewhere.
Our goats also LOVE dried apricots and prunes and hobnobs and digestives.
Happy goating.

Horses like goats too, they talk the same language.