Rules for kings to take pieces
Yes, a king can do that, but he has to land in between two pieces. If the diagonal had been b - - w w - - -, he wouldn't have been able to capture the pieces.

And yes, a king can change direction, but again, he has to land on the field where he changes direction. A player must capture as many pieces as possible.

There are many variants of draughts, as evidenced by the WikiPedia article. Pick one you like, or make up your own.