Those babies could be anywhere from two weeks to a month old. It's hard to say. By six weeks most rabbits are on their own 100%, but these rabbits probably need a bit of care for 2-4 weeks yet.
Your best bet is a wildlife rehabilitator. However not everyone has one of these around.
If this is the case in your situation I would put them in a pen with a bowl (not bottle) of water and some wild foods like they would find in nature. Dandelions, plantago, grass, nettle, clover, wild carrots, even some domestic plants like parsley, kale or alfalfa would be OK as long as it's a variety that grows locally. Don't touch them, just watch and see if the baby rabbits eat or drink on their own. If they don't, if they seem confused, clumsy or unconfident eating the food, they are likely closer to two weeks. If they confidently chow down on such a sudden and tasty abundance, they're likely closer to four weeks. Keep in mind, wild baby rabbits are VERY small! I don't know how big your hand is but I can hold two four week old wild rabbits like that in mine.
If they're closer to two weeks;
Rabbits this age are just starting to learn to eat solids. You will want to buy meyenberg goat milk and feed them once every NIGHT with this. If you can't get this you can try kitten milk replacer. Let them eat as much as they want in just a few minutes the first night and then wean them off of it in a week's time. The babies should end up on soilds very soon so make sure they still have LOTS of fresh wild edibles and fresh water. Keep them in a safe cage with minimal bedding (like newspaper) save for one corner which should have a cardboard box lined with something warm (finely shredded newspaper is fine, carefresh bedding would work, or even an old cotton t-shirt). You can also provide petstore or horse hay. Timothy and orchard grasses are the best. Don't touch them during the day and try to stay away. Minimize your interactions with them. Only keep them on this for about a week, and then move on to treating them like four week old kits.
For four week old kits;
Put the kits in the cage with the box outside for 24 hours with food and water, and them move them into just the box outside. Still make sure the box is full of nesting material. Make sure where you pick for them is well hidden and safe from predators, pets and children. Deep under a bush or some other natural-feeling safe spot it a good way to go. Leave out hay, wild edibles and water for the babies. When they feel ready they will find their own way. Kits leave their moms and are on their own very early. Don't be surprised if they're gone the very next day.
For kits of both ages;
Most animals aren't born with good bacteria in their gut. This bacteria is important for breaking down their food, and is normally gotten through their mother's milk. Not so in baby rabbits. Rabbits produce a type of poop that is re-ingested on a regular basis called "cecal" pellets (as opposed to their usual "fecal" matter). The baby bunnies get the bacteria in their gut from eating this from their parents. Since the parents aren't around you need to replace this somehow. The best way I have heard is using a Bene-Bac powder in their water, but I know there are other probiotic products that you can use.
Good luck!