The only way to learn logic is by practice. You need to build small apps using react native and then slowly you could get the logic understanding. Maybe data structures could give you some ideas about logic handling. Basic languages like C and Java are good languages to build up the basics of any programming language.
I also wanted to add another point. Brainstorming can help in bringing out new ideas, especially when you start from scratch. I recommend watching Live Code with Jesse on youtube, free code camp channel. Watch from the start of a project, so you will get an idea of how they break down features and other things necessary while building from the base.