#!/bin/bash
shell_variable=NewTag
shell_variable2=Backendapp

      awk -v val_shell="$shell_variable" -v name="$shell_variable2" '
    /:$/{
      flag=""
    }
    $0 ~ name {
      flag=1
    }
    flag && NF && (/ImageTag:/){
      match($0,/^[[:space:]]+/);
      val=substr($0,RSTART,RLENGTH);
      $NF=val_shell;
      print val $0;
      next
    }
    1
    '