They are very easy but a few pointers. Firstly you need to spend some time each day with them. Check food level and that fresh water is always available (not knocked over for example or evaporeated in the hot UK sun). Change bedding in nesting box from time to time. Move run from time to time as the ground gets soiled and very bare but soon recovers. Just dig it over as hen muck is very good for improving your soil. When you go on holiday you will need neighbour to look in on them ideally each day.
Food. Bag of proper hen food lasts ages. On top of that you can supplement with scraps, fresh food like green leaves(outer leaves of lettuce or stuff you collect from verges). They eat anything. Ours fight over shrews, a small snake once, slice of ham, leftover spaghetti)
You can let them out into your garden but you need to watch them as they are vandals. They love to dustbath to maintain health and that might be bang in the middle of your ornamental flower bed. Guinea fowl are far better behaved but make a LOT of noise and won't go into their run/hen house at night preferring house roof instead.
At the height of egg laying they lay one a day for maybe 250 days or more before moulting. That lasts a month or so before they start again. So if you have three birds that will give you around 15 to 21 eggs a week. You don't need a cockerel unless you want fertile eggs for hatching. Cockerels look and taste nice but otherwise just cosume food and amke a lot of noise unlike the hens.
Most varieties make good pets i.e. let children pick them up. They are not good at learning tricks or commands. Ours do know a few commands. OUT, come here and in you go. That is about all they bcan take on board.
Your eggs will never be as cheap as shop eggs and you may have a hen die unexpectedly from time to time but they live for quite some time(years). The eggs will however be much better taste wise and have no antibiotics etc in them.
You may find that mice or rats are attracted by the food but in reality they are there anyway but just not seen much.
Accomodation. As well as a run they will need a house to roost in(pole off the ground) and a nesting box ideally one per bird so they don't have to Q to lay. Even so you will find they all use the same box!
Hugh Fernley Whittenstall has a very good forum for poultry.
PM me if you need anymore info