Silk curtains first row - with goblet pleat, second row - curtains on rings; tulle.
The scene includes a simplified model of a window in the wall and a simplified model of a cornice. The colors of the model can be changed in the material settings.

https://3dsky.org/collection/shared/5255126  collection of my curtains.

For Corona render, it is recommended to use version no lower than 1.5, as the glossiness of the materials is set with PBR in mind.

If you are working in V-Ray version lower than 3.1, please be careful, in the materials section BRDF is set to Microfaset GTR (GGX), if your version is older, the BRDF field will be empty. Choose Blinn, Phong, or Ward - whichever is preferable for you.