If you ever worked with Spring Boot, then you are probably aware of Spring Initializr.
The Spring Initializr is a web application that you can use to create a Spring Boot application.
Do you know Spring Initializr itself is an open-source Spring Boot application?
You can fork it, customize it, deploy on your infrastructure and use it to generate Spring Boot applications.

Test

Spring Initializr is an open-source Spring Boot application powering start.spring.io. You can clone, customize, and self-host it to add custom dependencies or starters for your organization. The tutorial walks through cloning the repository, running it locally, adding a RestAssured dependency by editing the application.yml configuration, and then configuring IntelliJ IDEA Ultimate Edition to use the custom local instance instead of the default start.spring.io URL.

Running your own Spring Initializr and using it from IntelliJ IDEA

Using Custom Spring Initializr from IntelliJ IDEA Ultimate Edition