Curtains with goblet pleats with a tieback on one side and a trim on the inner sides of the fabric, tulle.
The scene includes a simplified model of a window in the wall and a simplified model of a cornice.
The curtain set is grouped for convenience. In the export file, all objects are ungrouped.
The colors of the model can be easily changed in the material settings.

https://3dsky.org/collection/shared/5255126  my curtain collection.

For Corona render, it is recommended to use version 1.5 or higher, 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, as the materials in the BRDF section use Microfaset GTR (GGX); if your version is older, the BRDF field will be empty. Choose Blinn, Phong, or Ward - whichever is preferable for you.