WEB-INF not included in WebApp using SpringBoot, Spring-MVC and Maven

You should create a .war rather than a .jar for a web application and you will see the WEB-INF folder.

Also change

spring.mvc.view.prefix=/WEB-INF/ to spring.mvc.view.prefix=/WEB-INF/templates and

ModelAndView("templates/test-block") to ModelAndView("test-block") to address the 404 error.