Sorry I've been MIA for awhile! This is a total newb question, but if they're not homers will they still fly back to their coop? I'm assuming all breeds of pigeons have some homing instinct.
I only have homers, but I am aware non-homing breeds, such as performance breeds like tumblers and high fliers, can be flown and trained to come back to the loft if released from the loft, not from far away like you'd do with homers on a toss.
That being said... One got away from me yesterday. I watched her circle above for a short time and then disappear. I've left the coop open for her to return with food on the loft, but it's been since 3pm yesterday and no luck. We had a hawk here a few days ago and I'm wondering if the hawk got her OR if she wasnt accostomed to her coop enough yet... It just concerns me because I don't want it to happen to another one
If it is a homer, it likely attempted to home back to its original loft. If that is the case, it might be found there eventually, or it could simply die trying to get there if it is too far away. If it is not a homer, and was not properly trained to learn how to get back to its loft, I'm not sure what the chances of it coming back are. The bird may not understand how to get back to its loft, and/or could have been hit by the hawk. Give it a few days, and make sure the loft is visible and the birds in your loft are also visible from a far.
Also, will they breed on their own if we have males and females?
Yes, given the proper resources (nest materials, nest bowls, calcium, etc) they should successfully. Even without the proper resources, the will likely still attempt to reproduce, just not with as high of odds of success. For example, they may try to build an inadequate nest using the best things they can find such as feathers and such, and make the nest on the floor, etc. They can still hatch squab this way though, but you'll want to give them the best shot they can get and provide nesting and breeding resources.