Printer ink is expensive. Really expensive. Every computer I know lets you change the print settings to default to black and white. But out of the box the default will invariably be to print color. Which is a huge waste of money.
Learn how to change the settings. I can't tell you here exactly how to do it, not knowing what software and hardware you have. But there is a way to do it and if you look in the printer manual or look online you will be able to figure it out.