Manual installation error

Good morning! I am wanting to install the platform but in all installations it throws an error in step ./configure. I already tried changing versions of Ubuntu 18, 20, Debian 10. In all it stays in --add-module = … / nginx-rtmp-module-1.2.1. I looked for the solution but could not find it. Is there an installation script?

Where are you getting ./configure from? The installer does all of that for you:
Standard Install | Open Streaming Platform Wiki