How realistic is Weight Training /Strength exercises after Surgery and during Chemo?

I wouldn't be doing any power lifting until the physio clears you. Especially since you have already had some complications.  Frustrating I know. Plenty of cardio you can do in the meantime if you feel well enough.

Cording is a tightness under the armpit and can run down to the elbow.  It is scar tissue.  Stretching is the best thing to prevent or improve it. If it becomes really tight see a physio experienced in this. Exercise and  Laser can help. You can see it, but sometimes just feel it.