Only Front end development is required as per the design shared by us. No Backend integration is needed.
Your scope of work is as follows. Please quote 

1. Re-develop 70-75 pages as per design shared by us.
2. Code the frontend with React.JS with excellent user interface experience, using Virtual Dom. Plus, the client side needs to be handled using local state management library like Redux
3. Integrate the API's that will be delivered by us .
4. Assume scope of work to be for 75-80 screens with search create, edit, delete options to be present.