I read the documentation of the metronics theme for light box use. and followed the steps but it's not working fine in the angular project.
May I know if you are referring to this docs page? The docs here is mostly only working for HTML version.
For angular, you may try this guide. To integrate fslightbox with Angular, you can follow these steps:
Install the fslightbox package using npm:
npm install fslightbox --save
import FsLightbox from "fslightbox";
lightbox = null;
this.lightbox = new FsLightbox();
this.lightbox.open([...]); // add your image or video URLs inside the square brackets
close()method of the lightbox instance: