Server Side Rendering & Security in NodeJS with "Static" Pages and SPA

Hi.

I looked at the NodeJS docs & it talks about server side rendering & applying security using the LAYOUT page as main & separate other content pages.

I am trying to build an SPA with NodeJS as server model. Setup SPA in NodeJS Project @ben here suggested that it cannot be done using the layout-content architecture. I need to add regular HTML pages.
I tried doing that, and it led me to two doubts:

1. How will the server side rendering work?
2. How will the page level security work?

From the docs, the requirement for both seems to be calling a server action under “server side data” section.

I have no knowledge of NodeJS and have just starting working on it. Can someone please help me understand how to get both these options working?
OR, is this even the right way - SPA in NodeJS in Wappler?
Ben also pointed out that with layout-content system, NodeJS somewhat acts like an SPA, but I am not entirely sure if that is actually the case.