Complex sentence: He did his graduation from Khalsa College, Mumbai, after which he moved to Khalsa College, Amritsar to do his Masters in Punjabi in 1958 which earned him the rank of university topper and a gold medal.
Split into simpler sentences: He did his graduation from Khalsa College, Mumbai, after which he went to Khalsa College, Amritsar to do his post-graduation in 1958. Later on, he did his Masters in Punjabi then which earned him the rank of university topper and a gold medal.