For Release Management Tutorials Follow the following Blogs.
Please follow the blogs in sequence moving from one to the next.

You can follow all the tutorials and finally setup a Jenkins Pipeline. The Jenkins pipeline is connected to a GitHub repository, whenver the source code is changed in GitHub, it will trigger the “compile” or “build” step in the Jenkins pipeline and then deploy it to the tomcat that you will configure.

Setup CentOS Virtual Machine

Relase Management: Setup Tomcat Application Server

Release Management: Setup Jenkins with Root Access and Maven and GIT

Release Management: GIT to Build to Deploy First Maven Project

Release Management: Jenkins Continuous Integration Pipeline From GIT to Tomcat