The FWHM or broadness of XRD peaks decides that your material is amorphous, semicrystalline, or crystalline..I am attaching a pdf that might helps you.

Yes. The best book

Crystal Structures of Clay Minerals and their X-Ray Identification

Author(s) G. W. Brindley; G. BrownMineralogical Society of Great Britain and Ireland📷Volume 5DOI: https://doi.org/10.1180/mono-5ISBN electronic: 9780903056373Publication date: January 01, 1980

Supriya Shetty

In your drawing, there is a broad peak of amorphous polymer and two peaks of crystalline nano or meso polymer. The amorphous peaks are very broad. The peaks of an ordinary crystal are very narrow, while the peaks of the nanoparticles are slightly broadened. See article for comparison

Article Physico-Chemical Properties of Nanoparticles Functionalized ...

if you get sharp peek it indicates crystalline