React Authentication

you want to use this starter project to develop commercial sites, themes, projects, and applications, the Commercial license is the appropriate license. With this option, your source code is kept proprietary.

Github

React: React is a widely used JavaScript library for building user interfaces and single-page applications. It follows a component-based architecture and uses a virtual DOM to efficiently update and render UI components
Firebase: Firebase offers a comprehensive set of features, including real-time database, authentication, hosting, cloud functions, storage, and more. Firebase provides an easy-to-use interface and allows developers to focus on building features rather than managing infrastructure.