How do I deploy my Jenkins build on a droplet?

I have Jenkins set up with nginx in a docker container on a droplet. I installed the plugin Deploy to Container on Jenkins. Now I need to set up a Tomcat server to deploy the Jenkins war file to.

So where does my Tomcat server go? And why do I need another server when I have a droplet already? Do I need a new docker container on my droplet for the tomcat server?

My Jenkinsfile deploy stage currently looks like this, but I need to context?

stage('Deploy') {
            steps {
                echo 'Deploying...'
                sh 'deploy contextPath: null, war: "/usr/share/jenkins/jenkins.war"'
            }
        }