Question: how to open a skp file in revit?
Answer: Create a family in the Family Editor. See Revit LT Families.
Click Insert tab Import panel (Import CAD).
In the Import CAD Formats dialog, navigate to the folder that contains the SKP file.
For Files of Type, select the SKP file type.
Select the file to import.
Specify the desired import settings. ... 
Click Open.