Boobs!
Seriously.
If you cannot bf for some reason then the hospital will provide formula initially.
It is recommended to not express until you have bf established and you supply has settled down. Otherwise you'll just be stimulating more milk production every time you express which isn't ideal for you.
Also, it is far better for baby to have a dedicated person giving feeds and not have other people doing it. Other people can help with bath time, anppies, cuddles, taking baby for walks, doing your washing, making you dinner. REally, if you want to bf then it is better for oyu and baby to support you to feed rather than take over the feeding.
If later on down the line you want to introduce a bottle then generally speaking the ones that come with sterilisers etc are a pile of cack as they are very stiff. Plus they are expensive. You don't need all that stuff. Cheap bottles like oyu get int eh chemist with latex teats are jsut fine. YOu can sterilise in an ice cream tub and a milton tablet,cold water sterilising is great. fill the tub, stick the bottle in, ready in 20 min and can stay int he water for 24hrs until needed.
As for pumps etc, it varies. Hand expressing is great too and many peope find it much better than a pump. You should be shown how ot hand express before discharge so make sure you ask.
What I'm trying to say is don't go out and buy a load of stuff. Unless you are really isolated then you can get it as and when you need it. All you need to bf is one breast. You don't even need 2! Some comfy crop top style bras are a good idea until your supply and therefore size has settled and some breast pads for leaking, though not everyone leaks so don't go mad, again, you can always buy more if you need them. People will say you need lansinoh but you only need it if you have trouble with positioning and attachment and get sore,with good support then you shouldn't and if you do then your MW should be able to give you some samples!