Multibranch Pipeline Jenkinsfile 'cmd' is not recognized as an internal or external command, operable program or batch file

Question

I am working on Jenkins [Multibranch Pipeline]. I configure the GitHub and its working fine.But I am facing an issue when I am trying to deploy the GitHub project to SALESFORCE production. I also placed Jenkins file in GitHub project. Here is the code of my Jenkins file

    #!groovy
import groovy.json.JsonSlurperClassic
node {

    def BUILD_NUMBER=env.BUILD_NUMBER
    def RUN_ARTIFACT_DIR="tests/${BUILD_NUMBER}"
    def SFDC_USERNAME

    def HUB_ORG=env.HUB_ORG_DH
    def SFDC_HOST = env.SFDC_HOST_DH
    def JWT_KEY_CRED_ID = env.JWT_CRED_ID_DH
    def CONNECTED_APP_CONSUMER_KEY=env.CONNECTED_APP_CONSUMER_KEY_DH
    println 'KEY IS'
    println JWT_KEY_CRED_ID
    println HUB_ORG
    println SFDC_HOST
    println CONNECTED_APP_CONSUMER_KEY
    def toolbelt = tool 'toolbelt'

    stage('checkout source') {
        // when running in multi-branch job, one must issue this command
        checkout scm
    }

    withCredentials([file(credentialsId: JWT_KEY_CRED_ID, variable: 'jwt_key_file')]) {
        stage('Create Scratch Org') {
            rc = bat returnStatus: true, 
            script: "${toolbelt}/sfdx force:auth:jwt:grant --clientid ${CONNECTED_APP_CONSUMER_KEY} --username ${HUB_ORG} --jwtkeyfile ${jwt_key_file} --setdefaultdevhubusername --instanceurl ${SFDC_HOST}"
            if (rc != 0) { error 'hub org authorization failed' }

            // need to pull out assigned username
            rmsg = bat returnStdout: true, script: "${toolbelt}/sfdx force:org:create --definitionfile config/project-scratch-def.json --json --setdefaultusername"
            printf rmsg
            def jsonSlurper = new JsonSlurperClassic()
            def robj = jsonSlurper.parseText(rmsg)
            if (robj.status != 0) { error 'org creation failed: ' + robj.message }
            SFDC_USERNAME=robj.result.username
            robj = null

        }
    }
}

I am trying to authorize salesforce by useing this line of code.

rc = bat returnStatus: true, 
            script: "${toolbelt}/sfdx force:auth:jwt:grant --clientid ${CONNECTED_APP_CONSUMER_KEY} --username ${HUB_ORG} --jwtkeyfile ${jwt_key_file} --setdefaultdevhubusername --instanceurl ${SFDC_HOST}"

But when i run jenkins I am getting this error.

'cmd' is not recognized as an internal or external command, operable program or batch file.

I WILL APPRECIATE IF ANYONE WILL HELP ME