You can assign different views to each of the 2 viewports by selecting a view from the drop-down menu in the upper corner of the viewport.
You can also maximize individual viewports by clicking the expansion/contraction icon. To return to 2 viewports, click it second time:
To change your view in perspective view, click and drag in the viewport using the mouse:
- Right and left mouse click and drag to rotate in perspective view.
- Mouse wheel (or middle mouse scroll) to zoom in and out.
- Double press middle mouse to reset the view to its default state.