Hii..

As you ask about best website and best way to get knowledge about MBA ,about management  skills and other important skill related to MBA...

so you can go through careers360 link to get information about MBA, about MBA colleges ...

about other skills there are many other online courses site that's make help you to develop skill of MBA like udemy ,coursera, EDX and other online  websites.

so you can go there you can use that's website to enhance your knowledge...

All the best!!