Shiny Server - Losing my mind - Can't get things working?

Hi all,
New to linux, new to Shiny Server, but a long time R user on Windows so I know I'm doing something wrong, I just don't know what.
I'm running on RHEL 9, and Shiny Server and R are both successfully installed, and have the Shiny package downloaded and running.
I am fairly confident that the issue is my Shiny Server is not pointing to the R Library, but I don't know how to change that.
According to the docs (Shiny Server v1.5.22 Configuration Reference) -

To allow Shiny Server to search for R in additional locations, you must alter the file in /etc/init.d/shiny-server or /etc/init/shiny-server.conf , depending on which startup system you’re using (as discussed in Stopping and Starting. You can either adjust the PATH variable to include the directory where R will be found, or you can set an environment variable named R to tell Shiny Server exactly where it should look for the executable.

I have looked everywhere and cannot find the /init/ folder. Is this something I have to set up?

When I open the index page in the /srv/shiny-server/ folder, the page opens and says Shiny Server was successfully installed, but the shiny app and rmarkdown samples both have the directory view rather than the actual app (which makes me think it's not seeing the R I'm using).

Any ideas? I need to get this server up and running for a big meeting next week and can't believe this is what I'm stuck on.
Thanks
Chris