After the Enscape .exe installer has finished running and has been closed, you should then be able to see Enscape as a top level menu option within Revit’s top level menu structure within its User Interface (UI).
If you can see the Enscape top level menu option, then clicking on it should result in the Enscape ribbon becoming visible, as shown in the following screenshot.
Location of the Enscape menu in Revit
Starting Enscape in Revit
You will notice that at first not all the buttons are active and this is because you must first perform the following:
The view’s associated phasing and design option is used for Enscape’s view.
You can leave Enscape open while you make any desired changes in Revit (e.g. cross sections, materials or geometric changes in the model).
Your changes will show up instantly in Enscape.