Complex sentence: Before making his debut as a film director he assisted Kunal Kohli in Fanaa, Ta Ra Rum Pum and Thoda Pyaar Thoda Magic who also produced his debut film Break Ke Baad which stars Imran Khan and Deepika Padukone.
Split into simpler sentences: Before making his debut as a film director, he assisted Kunal Kohli in Fanaa, Ta Ra Rum Pum and Thoda Pyaar Thoda Magic. Kunal produced his debut film Break Ke Baad starring Imran Khan and Deepika Padukone.