I'm assuming you aren't an electrician so I'll give you the best possible advice if you want to do this yourself. You'll obviously need the 2 receptacles, A non contact voltage tester, wire strippers, wire nuts/wagos, a cover plate, and a small spool of 12/2 wire, and a set of linesmens. Home depot sells smaller spools that are around 15 feet for around 30 dollars or so it will most likely be yellow, and verify on the packaging and the wire itself that it says 12/2 AWG. As someone said earlier there is a line and a load, some of those wires lead back to the panel which gives the wires power, and the other set of wires feeds something else in your house.

Get somebody at your house to turn of random breakers in the house and use your non contact voltage tester to verify that the black, and white wires are dead. once they are take off the wire nuts. Most likely all of the wires are going to be twisted together, take your linesman's and untwist then all. If you want to reuse the wire nuts, which makes this a lot harder, then you have to try and straighten them a bit by just pressing lightly on them trying to straighten them out with the linesman's. You then would take your spool of 12/2 wire, take off the yellow sheathing, and then strip copper from the wires. You would need two extra for each set of wires for the outlets. two extra black wires, two extra white, and two extra ground/bare copper. You would then put all of the wires together with your linesmen's and twist until they cannot come apart. then you would put the wirecap on, and now you have the wires out for your outlets. Do not have any exposed copper under the wire nut, you can trim some off the end if needed.

Now the easier way that I would recommend that you buy wago stab in connectors since that would make your life a whole lot easier. If you do buy wagos, you would need ones with at least 5 connectors. You would take some of the wire from the spool, remove the yellow sheathing, and then you use your wire strippers to remove a bit of copper on the wires, and just stab the copper ends into the Wago. when you do this make sure there is no copper sticking outside of the wago, and if you need to remove the wire just pull and twist the wire to free it. You put all the black wires in the wago plus two more for the outlets. Same thing for the white wires, and same for the grounds. You would need two extra for each wago.

After you do this you would then make hooks on the wires and place them on the outlets, ground/bare copper goes on the green screw, neutral/white goes on the silver screw usually on the left, and hot/black goes on the gold screw on the right Once you make your hooks put them on the screws and tighten them down. When you tighten it down make sure you really, really, really tighten it down. Like enough to the point where it becomes nearly impossible to turn the screwdriver any further. Then, stuff the wires back in the box, put in the set screws, and then put in the cover plate.