That is a lot of info you need Aidy and it would be worth googling rabbit care to get more details unless someone here can point you to a good site.
However, the basics. What sex and age are the bunnies and are you confident that the person who sexed them knows what they are talking about? I ask because I know of countless people who have bought 2 girls or boys then found out they are one of each, usually when one of them is already pregnant. Male rabbits really need castrating once their testicles have descended. (I think around 3 and a half to 4 months). Even if you have 2 boys together I would still get them neutered as they may fight. Not many people in the UK get the girls spayed as well though opinions differ as not doing so increases risks of gynae cancers etc. Unfortunately it is not cheap. (Around 60 - 70 quid where I live).
Make sure they have fresh water, and most importantly hay. A bunny diet should be around 75% hay with other food in small amounts. Stick to whatever food they are currently on
and introduce new foods gradually. Bunnies have very complicated digestive systems which are easily upset and diarrhoea can kill a bunny, particularly a baby. You can use a dry food such as supa rabbit excel which is pellets that all look the same and stops selective feeding. I just use a standard and cheaper bunny brunch but don't give too much and my bunnies eat it all. Obviously small amounts of greens and carrots can be given too.
Mxyamatosis shuld be vaccinated against. Where I live the vets advise it every 6 months but in some areas once a year might be enough. It depends how prevalent mxyi is in your area but your vet will advise you. There is another deadly disease. viral haemmorhagic disease that you can vaccinate against. Again your vet can advise if he feels it is necessary. I don't think VHD is very prevalent in the UK but it is highly contagious. I have never heard of a rabbit dying from it in my area.
Generally, check the rabbits teeth. the front teeth should be straight and even otherwise they can have problems chewing. Often vet nurses can do teeth checks and they can be free of charge. Check their bottoms are kept clean and dry or fly strike can occur which will be fatal if not caught quickly. This is more likely in older infirm buns but some bunnies are not good are cleaning themselves so look out for this. I just check my bunnies look ok every morning, that they are eating and have pee'd and poo'ed and running around. A bunny hunched in a corner is usually a sign of a poorly or injured bun.
Thats the basics I think but I don't want to overwhelm you
If you have any specific concerns let us know and we will attempt to help.