Most of my 5th toe is dry gangrene some part is okay. doc advised me to wait & watch it. my toe feels detached & hasnt been reduced properly. ?

Watch for Change.: Taking your information at face value, the doctor who gave you this advice is right. He is probably waiting to see if the toe will demarcate between viable and dead tissue. You need to follow his advice and watch for infection. It may need to be debrided(reduced), as you say, some time in the future. You age is concerning as to just what happened to your toe and why did gangrene occur.