Double curtains with goblet pleats and tulle. The inner fabric is tulle with a tieback. The outer fabric is a dense curtain.
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 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, be careful, as the materials in the BRDF section have Microfaset GTR (GGX); if your version is older, the BRDF field will be empty. Choose Blinn, Phong, or Ward – whichever is preferable for you.