Add vlc installation to application

Hi to all, I'm completelly new to nsis,
So, tank you for any help

I have an application witch I can zip and sucefully convert to installer with nsis.
This app needs vlc installed so I'm trying to understand how to add an installing-request of vlc during app installation.

I found these two scripts, both talks about vlc snis installation
1. from snis wiki:
https://nsis.sourceforge.io/VLC_media_player
2. from vlc github repository:

https://github.com/videolan/vlc/blob/master/extras/package/win32/NSIS/vlc.win32.nsi.in

They don't work passed as scripts in snis, but I'm pretty sure they are not to be used standalones.

First of all I can't understand nsi.in extension (what is it and how can I use them?)

Trying to pass to nsis these scrpt I found error: Invalid command: "@HAVE_WIN64_TRUE@"

can someone can halp me to understand or suggest some guide about this functionallity?
tank you.