This video helps to understand , how you can create a tomcat deployable war file from a spring boot application.
To create a Tomcat deploy-able war file from a spring boot application make sure your packaging style in pom.xml file is war.
Then go to your project location in your local system and open a command prompt and execute the following command
mvn clean install -DskipTests
after the build is successful go to the target folder of your project then you can find the war file.