Day 78 : Jenkins - Validation file not found on app server

what exactly is need as per task , i am unable to get requirement & solve error.

I do not why i am failing because i have done around 30+ times but i could not where i am failing . below are things & attaching screenshots.

IN stapp01 i have excuted below
yum install java-17-openjdk -y
sudo chmod 755 /home/sarah
sudo chown -R tony:tony /home/sarah/jenkins_agent
sudo chown -R tony:tony /var/www/html

script :pipeline {
agent {
label ‘stapp01’
}

parameters {
    string(name: 'BRANCH', defaultValue: 'master', description: 'Enter master or feature')
}

stages {
    stage('Deploy') {
        steps {
            script {
                if (params.BRANCH == 'master') {
                    sh '''
                        cd /var/www/html
                        git fetch --all
                        git checkout master
                        git pull origin master
                    '''
                } else if (params.BRANCH == 'feature') {
                    sh '''
                        cd /var/www/html
                        git fetch --all
                        git checkout feature
                        git pull origin feature
                    '''
                } else {
                    error("Invalid BRANCH value: ${params.BRANCH}")
                }
            }
        }
    }
}

}


refer to this solution