Jenkins Pipeline with the parallel stages

Jenkinsfile.groovy

pipeline {
    agent any
    
    stages {
        stage("Deploy") {
            parallel {
                stage("dev") {
                    when {
                        beforeAgent true
                        expression {
                            params.DEPLOY_DEV == true
                        }
                    }
                    steps {
                        echo "Deploying to dev"
                    }
                }
                stage("staging") {
                    when {
                        beforeAgent true
                        expression {
                            params.DEPLOY_STAGING == true
                        }
                    }
                    steps {
                        echo "Deploying to staging"
                    }
                }
                stage("prod") {
                    when {
                        beforeAgent true
                        expression {
                            params.DEPLOY_PROD == true
                        }
                    }
                    steps {
                        echo "Deploying to prod"
                    }
                }
            }
        }
    }
}