The Content panel takes up the majority of the RouteBuddy Window to the right of the Source List.
It is comprised of two main areas depending on the Source List function selected.

When the mouse is hovering over the Map View Area and you do a right click you are offered a contextual menu.

If you have an feature item (e.g. a route) selected when you right click you will be offered a contextual menu applicable to the feature.

The columns in the Browser View can be reordered by using the flippy triangles at the top of each column, they can also be expanded.
If nothing is highlighted in the Browser View Area a right click of the mouse will enable you to:
If you have an feature item (e.g. a route) selected when you right click you will be offered a contextual menu applicable to the feature.
The majority of time you will be working with your maps in a Place file. When viewing a Place File the Content panel shows the very distinct areas of the Map View area and the Browser View area as can be seen below:
The Map View will show an area of Map and the Browser View will display all waypoint, route and track items held in the Place file.
Refer to each of the Source List functions to see how the Content Panel changes according to the selected function.