Build me a React Native app for Android and iOs

I am a Small Business in the Alternative Medicine domain. We are in the retail space of raw herbs and spices, as well as preparing certain alternative formulations on request. This app is a private project funded by us, for the growth and upliftment of herbal medicine all over the world. What we need is below - - The App will contain 5-7 pages, and the front end (or the layout is very simple). - Backend is mostly about fetching data so search speed is very important. - There will be some quick calculation involved as well as dynamic on-screen content (not visual changes, just numbers and texts)