Rebuild a current WebApp using modern framework

We are looking for a freelancer to Rebuild our custom web application that we have, the Application is built using Bootstrap, with a SQL database and has some Angular. We are looking to rebuild the application using Laravel for the backend and open to discussion on the frontend. The current application is live and in use but the rebuild will be a completely new code base, we wish to keep the existing functionality of the application but also add extra functionality as well as fix some areas that are not working in the current application.