He had done his graduation from Government College, Lahore and later took up flying as a passion at Walton Aerodrome in Lahore from where he earned a flying licence. Later, he joined the Royal Indian Air Force and was training at Karachi flying Howard aircraft when his father, Major Harpal Singh Gill, withdrew him from training because the family considered flying to be unsafe.

Colonel Gill thereafter joined the Navy where he served on a mine sweeping ship, INS Teer, which was an escort for cargo ships during World War-2. He subsequently left the Navy after having completed the Long Range Gunnery Course in which he was graded Instructor Gunnery (IG).

Colonel Gill joined the Indian Army soon after Independence and sought placement in 1 Sikh (now 4 Mech) in which many members of his family, including his father, had served. However, due to his gunnery experience he was allotted the Regiment of Artillery and posted with Gwalior Mountain Battery equipped with 5.4 inch guns.

(With inputs from agencies)