Canon printer MG2150..colour cartrige is empty and black and white is full how do i print from it???

You have discovered the real secret in printers - they are designed to print ONLY when there are detectable levels of ink in all cartridges. This forces you to buy new cartridges even if you only want to print black.

You can try setting the printer settings to black and white in the properties, but I wouldn't hold my breath.

Now you know why printers are "cheap" - they're gonna get you with new cartridges that cost as much as the printer. I always buy the cheapest printer I can find and then pitch it when the ink runs out.

Mark