Calculator for invoice using javascript

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.6.3/jquery.min.js"></script>

<script>

       function totalPrice($val){
                    let amt = 0;
                    let arrlength = 1;
                    let arr = document.getElementsByName('owner_shares');

                    for(let index = 0; index < arr.length; index++){
                        let price = arr[index].value;
                        amt = +(amt)+  +(price);
                        arrlength = arr.length;
                    }
                    document.getElementById('profitpk').value = amt;

                }

                

                function  get_profit(){
                   let fixed_cost = $('#fixed_cost').val();
                   let urgent_cost = $('#urgent_cost').val();
                   let target_sales = $('#target_sales').val();
                   let add =  Number(fixed_cost)+ Number(urgent_cost);
                   let profit = Number(target_sales)-Number(add);
                   let amt = 0;
                    let arrlength = 1;
                    let arr = document.getElementsByName('owner_shares');

                    for(let index = 0; index < arr.length; index++){
                        let price = arr[index].value;
                        amt = +(amt)+  +(price);
                        arrlength = arr.length;
                    }

                   let total_profit = profit/arrlength;
                   // alert(total_profit);
                   document.getElementById('profits').value = total_profit;
                   // document.getElementsByClass('owner_shares').value(total_profit);
                   $('.owner_shares').val(total_profit);
                }

                function urgent_cost_change(){

                }

                function target_sales_change(){

                }

                 $(document).ready(function(){
                       $(document).on('click', '.addbtn', function(){
                          $('.duplicateForm .duplicate:last-child').clone().appendTo('.duplicateForm');
                      });
                  });

                  $(document).ready(function(){
                      $(document).on('click', '.dltbtn', function(){
                         if($('.duplicateForm .duplicate').length > 1){
                              $(this).parents('.duplicate').remove();
                          }
                      });
                      myFunction();
                  });

              </script>