Oh ouch, Sheila! Fingers crossed that it's not a stress fracture! But if it is and your doctor says it's OK, there's lots that you can still do.
I have a client who had a stress fracture in her foot last summer and worked out with me for two months while on crutches. We were able to do lots of upper body - seated, not standing. Actually, I can't think of any UB exercise that we couldn't adapt ... As for legs, she was allowed to do extensions, seated and lying curls, and the inner and outer thigh machines since none of those involved pressure on the foot. We used 2 1/2 pound ankle weights for front and side lying leg lifts and used a resistance ball for hammie curls and leg lifts. Leg press was obviously out.
I don't remember if you work out at home or in a gym. If it's a gym, you should be just fine. If it's at home, legs may be a bit more challenging, but you may be able to do some exercises with ankle weights and a resistance ball.