Create a Spring Boot project using Maven or Gradle, and add the necessary dependencies such as Spring Data JPA, Spring Web, and Thymeleaf.
Use JPA to create entities for Car, User, and Booking, and define their relationships.
Create repositories for each entity, and use them to perform CRUD operations on the entities.
Implement a RESTful API for handling user registration, login, and booking management.
Implement Spring Security for authentication and authorization, and use it to restrict access to certain API endpoints.
Use Thymeleaf to create the front-end views for user registration, login, and booking management.
Implement search functionality for users and cars.
Create a scheduler to update the status of booked cars based on their booking dates.