This is the links I think who can help you getting an app done in react-native. Remember for learning react-native you need to know React and his ecosystem. After that, almost 50% to 60% of the job is done, the rest gonna learning specific platform api.
I also have a youtube channel where I do small little clone of some website like twitter or instagram.
Twitter Clone: youtube.com/playlist
Instagram Clone: youtube.com/playlist
Hope that can help you.
Also I have this repos where I keep track of all the link he took me to learn react, react-native, redux etc github.com/EQuimper/All-About-Programming