Complex sentence: The Institution of Engineers (India) has more than one million members in it's 15 engineering disciplines in 125 centers or chapters located in India and overseas; it is the world's largest multi-disciplinary engineering professional society in engineering and technology world.
Split into simpler sentences: The Institution of Engineers (India) has more than one million members in its 15 engineering disciplines across 125 centers and chapters located in India and around the world. It's also the world's largest multi-disciplinary engineering professional society in the engineering and technology world.