Mom fractured ankle:her fibula and tibia. She is 64 and had surgery. At her age, will she be able to heal back to normal and be able to walk like before?

Mom with fx. Pending on what co-morbidities she may have, she may heal well and be able to walk like before, but no guarantees.

If physical therapy/occupational therapy is offered, do have your mom accept them. It will help her.
64 is not "old" 64 y/o is not "old"! I'm 63y/o and yes, if she is healthy, with no underlying problems like: diabetes, poor circulation, long time cigarette smoker, or cancers, she should recover and be able to do everything she was doing before injury. Be patient, it does take time to heal. I broke my Tibia and Fibula a few years back and it took a good part of two years after surgery with physical therapy.