Help me, please!!!

Please, can anyone make us a tutorial how to properly start the react native app? I need it just to learn the "good practice"...How can i make a fake api, or something just to bypass the login page and have access to the rest of the app?? I don't need the voice server, i just want to learn how to use navigation, typescript and the way how Ben was writting this app. I'm stuck at "Going to the moon...." screen. Thank you!!!