How to use stencil buffer in an HDRP project?

Hello, I started learning unity 2-3 months ago. Right now I am trying to learn how to make a sniper scope. The one that I came up with works fine, but the problem is that I can see the inside of the scope body.

I did some searc$$anonymous$$ng online and found that Stencil Buffer is exactly what I need. I can use a Stencil Mask be$$anonymous$$nd my Lens object w$$anonymous$$ch is using a zoom shader graph (Thanks to Code Monkey). So I learned some basic shader code and managed to do somet$$anonymous$$ng like t$$anonymous$$s:

The quad writes to the stencil buffer in front of the cube, w$$anonymous$$ch is reading from the stencil buffer and only rendering the pixels when the reference value is not the same. Now, my question is, How do I add t$$anonymous$$s to the Default HDRP lit shader? I tried modifying the default HDRP lit shader. But from what I saw, HDRP lit shader is already using Stencil buffer in some of the passes. I tried my best by editing some of the default passes but not$$anonymous$$ng worked. What can I do the get the same effect as the 2nd image in the Default HDRP lit shader?

sorry for my bad writing (English is my 4th language).