Complex sentence: His father, Naresh Sharma was a leading music arranger having worked with almost all the top composers in more than 200 movies and his uncle Pyarelal-ji (Pyarelal Ramprasad Sharma) formed one half of the legendary composer duo Laxmikant-Pyarelal.
Split into simpler sentences: His father, Naresh Sharma, was a leading expert of musical arrangements, having worked with almost all of the top composers in more than two hundred movies. Mithoon's father and his uncle Pyarelal-ji (Pyarelal Ramprasad Sharma) formed one-half of the legendary composer duo Laxmikant-Pyarelal.