How to fix support apple.com/mac/startup

How to fix MacBook not opening support.apple.com/mac/startup. MacBook pro won't turn on black screen ************************************************************************************ If you are really interested in my video please follow me on YouTube and Facebook …………………………………………………………………………………………………. Subscribe to my channel:    / channel   FACEBOOK GROUP:   / 411530109484518   FACEBOOK PAGE:   / itmagicsbd   ………………………………………………………………………………………………….. Background music:    / channel