Initialize localhost API

What command do I use to initialize localhost API?

What do you mean?

I want to launch the localhost application but by running make:

make: *** No targets specified and no makefile found. Stop.

So lib-jitsi-meet is a library and there is no make file, checkout its readme.
There is a webpack-dev server for jitsi-meet to experiment with UI and the app. The repo is and you need to execute

npm install
make dev

to run it.