Anytime you have a lower body injury where you can't put weight on your feet, you can maintain aerobic conditioning using just your arms with a bike that has moveable arms, like a Schwinn Airdyne.
If your gym doesn't have a bike with moveable arms, talk to you doctor about deep water aerobic training (so your feet stay off the ground) once your stitches heal. You can do water running and swim laps in about 8 feet of water.
Aside from conditioning, maintain strength by doing your upper body exercises seated on a bench, but take this opportunity to mix up your sets, reps, and rest periods for a new challenge.
And keep your core strong and movements where you lie on your side and on your back, like glute bridges. For bridges, instead of placing your feet on the floor, put a foam roll under your calves, keep your legs straight, and then bridge up. This will help keep your hips and torso strong without putting pressure on your foot.