What do you suggest if my father had a stroke last month, says he has a lump on rt.side from shoulder on down to elbow, says real soft?

Seek medical attn: Most likely this "lump" is unrelated to his stroke, but the only way to know what is going on is to be evaluated by a medical professional. If he was placed on blood thinners for his stroke it is possible that it could be a hematoma, but again he would need to be seen by a physician to determine this. Recommend he see his primary care physician for evaluation.