Step 1 Create a Maven project with Spring-Tool-Suite

• Select File --> New --> Maven Project
• Check Create a simple project(skip archetype selection). Then select the work-space for your project, which may be an empty folder you created manually for the project. Or you can use the default location by checking Use default Workspace location
• Click Next
• Input [Group Id], [Artifact Id] for the project.

  One example may be 'Group Id = com.mycompany.hello' & 'Artifact Id = st_a'

• Click Finish to let Spring-Tool-Suite` to build the project for you.

Step 2 Configure the pom.xml for you project

• Initially, the pom.xml automatically generated may contain content like

<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.mycompany.hello</groupId>
  <artifactId>st_a</artifactId>
  <version>0.0.1-SNAPSHOT</version>
</project>

• Add below section to declare a parent-project for it.

    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.0.3.RELEASE</version>
    </parent>

• Add dependency section to include Spring-boot

    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter</artifactId>
        </dependency>
    </dependencies>

• Add build section to include spring build plug-in

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
            </plugin>
        </plugins>
    </build>

Step 3 Create a package inside the project

• In the Project Explorer, right click on src/main/java, select New --> Package from the context-menu
• Input name for the package, like 'hello', then click Finish
• The coming steps are straight-forward, just follow the referenced guide and finish the task.

Step 4 Add the scheduled task class

• Right-click on the hello package just created, and selelect New --> Class
• Follow the spring-guide to create the class.

Reference

• Spring official guide