How can I add a new vertex in blender 2.8? When I click &#9096; Ctrl+ LMB to add a vertex, nothing happens.

How can I add a vertex in 2.8?

For now I merged mesh vertices at the center and extruded from that. 

However I am not sure if this would cause any problems.
It's ctrl+ RMB now. You could always create a face and delete the other three vertices.