From the turtlebot tutorials, I could create a map through teleop and then do the navigation of that known map where we can specify the destination point with in the known map.

How to merge these two aspects, i.e

When launched, the turtlebot should start keeping moving forward avoiding the obstacles building the map on the go which can be visualized through rviz. If we provide a dynamic navigation goal, even while creating the map, the turtlebot should start moving to that goal.