Checkout blog here https://xamarinmonkeys.blogspot.com/2020/06/xamarinforms-working-with-pdfview-and.html
PDFView doesn't support the default webview in android xamarin forms.
PDFView is the biggest issue in android webview. I solved this problem by using google drive viewer and google doc viewer there is another way to view pdf files using pdfjs. But pdfjs doesn't support pinch zoom.
The pdf URL must be an extension, PDF, and public.
You can test Pinch zoom by emulator also use Shift + ctrl + Left click and mouse move
Simulator also supports pinch-zoom use Alt + Left click and mouse move
