Ok they are baby babies and are probably just weened or in the process of being weened.
They ride Mamma because they are still learning from her and depend on her.
You can get them out individually but the babies will probably do better together and it will give Mom a break since Dad isn't there and she gets no other breaks like she should.
When I had joeys that young I started handling them as soon as they came out of pouch with their eyes closed for just a few minutes and worked up to keeping them out longer as they grew. If the babies fussed and cried for mom I'd put them back in with Mom n Dad. I'd get them out during the day mom n dad would usually go right back to sleep, unless the babies fussed.
When I'd get mom out I'd leave the babies with Dad so Mom would get some free time. For you I'd either have the babies in a pouch so you can reasure mom they are ok and she can check on them or have another family member hold the babies while you have mom. Then when your done with mom on her own let her go in the pouch with the babies and do bonding bag time with all of them.
It's ok if the babies sleep a lot they are young and growing, even when you have them out they may fall asleep in your hand n thats ok. They are still getting your scent while they sleep.
If you start working with them every day you will have some veryyyyyyyyyyyy easy to handle babies, though Mom may not be as easy as the babies. They are young and you are going to sort of imprint that you are safe as they grow where as mom is already an adult and may need longer to "bond"
Take it slow, be patient, get on a routine, and seriously enjoy them at that size and age it passes quickly and before you know it they are teenagers.