The pom.xml is correct. It seems that there is a network issue. The plugin was not downloaded due to that.
Steps to solve the issue :

- Right click on the project >> Run As >> Maven install (this will download all dependencies and generate target folder).
Example :

- If problem still persists, then last option is to force refresh of the project. Right click on the project >> Maven >> Update Project.

- Update Maven Project Window will be come.

Note: Enable the option Force update of Snapshot/Releases (look in above screenshot). By default, this option is not enabled. Click on ok. It will start updating.
- Open the Maven tab present on the right tab and check for spring-boot-maven-plugin.

- If the plugin was not downloaded, then click on clean maven lifecycle and it delete the folders that were generated by maven.

- Then, click on install maven lifecycle and it will download all the dependencies and generate all the folders from scratch required for the project.

- Last step is to force update of the project. You need to click on the Generate Sources and Update Folders for All Projects option.

Note : Go the Preference -> Build, Execution and Deployment -> Build Tools -> Maven -> Enable "Always update Snapshots" option present -> Click on Apply and Ok. This option helps sometimes.
Download maven from here and extract it.
Set maven location on the environment variable so that it can run from anywhere.
Open CMD/Terminal and then do mvn clean install inside the project.
Update for viewers: <version> tag is not mandatory tag to be there for spring-boot projects because pom.xml created by spring for spring-boot can handle the version of the spring-boot-maven-plugin.
Updated pom.xml :
<?xml version="1.0" encoding="UTF-8"?> <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 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.3.5.RELEASE</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>dev.che</groupId> <artifactId>stu</artifactId> <version>0.0.1-SNAPSHOT</version> <name>stu</name> <description>Demo project for Spring Boot</description> <properties> <java.version>1.8</java.version> </properties> <dependencies> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jpa</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> <scope>runtime</scope> <optional>true</optional> </dependency> <dependency> <groupId>com.h2database</groupId> <artifactId>h2</artifactId> <scope>runtime</scope> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> <exclusions> <exclusion> <groupId>org.junit.vintage</groupId> <artifactId>junit-vintage-engine</artifactId> </exclusion> </exclusions> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> </plugins> </build> </project>
Edit :
If above steps are not solving your issue, then you can go for the workaround solution by explicitly providing the parent spring boot version in the plugin for spring-boot-maven-plugin (not a recommended solution):
<plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <version>${parent.version}</version> </plugin> </plugins>
mvn compile?