Size of cage depends on how much out-of-cage time they will realistically get every day. The two factors go hand-in-hand. But for a general idea, check the 2022 cages thread. The first post details the general guidelines (applies to 1 or 2 rabbits) recommended by various organizations.
Each year we start a new thread to show off our rabbit cages. Not only is it fun to see everyone's cages, it is also useful for new bunny owners. Whether you've made a cage out of cube grids, exercise pen, xl dog crate, old furniture or any combination, we'd love to see it! (there is a separate...
Hopefully both of your rabbits are fixed? Here is some further info on bonding: