Webview print: how could i activate?

I have a webview apk, inside my website there is an add-on to print the files, I wanted to know how it is possible that when my users click on the printer the pdf is printed by the phone itself, the storage permission I have already created.

I need this information too.

Maybe you can give it a try:

You may get confused by how to use the extension, so here a very basic guide.