Design an app and a website with backend and frontend support

My project consists of creating an app and website to support online bidding. This app should provide users with an efficient and secure platform to post bids and compare different options. It should have a modern design which should be attractive and easy to use so that users can quickly navigate around the app and website with ease. I estimate that the app and website should have approximately 6-10 pages/screens. The app and website should also have an efficient frontend and backend support system for an easy and secure user experience. Ultimately, I am looking for a developer who can create an app and website that will allow users to easily and securely post their bids on the app and website.