Im trying to download a file and i need to send option to my Django view from js script . Please advice

My HTML page looks something like below:

The post function used is for upload the file with edited data..!
Im trying to get the option value from HTML page to my Django view.

<div><h3 style="text-align: center">Bulk Upload</h3></div>
<form action="" method="post" enctype="multipart/form-data">
      {% csrf_token %}
    <div class="col-md-4">
    <select  class="form-select form-control" style="padding: 3px; border-radius: 1px;" id="option" name="option">
      <option selected value="0"> Please select operation</option>
      <option value="1">Insert New Source Client</option>
      <option value="2">Update Volcker Attribute</option>
    </select>
    </div>
    <div class="col-md-2">
    {% csrf_token %}
    <button

            id="downloadBtn"
            type="submit"
            title="Download CSV Template"
            onclick="export_template()"
            class="btn btn-primary"
            style="height: 34px; width: 100px"
    >
        Download
    </button>
    </div>

My javascript function is defined as below:

function export_template(){
        let option = document.getElementById('option').value;
        console.log(option)
            if (option!=""){

                window.location.href="export_template/option="+option;
            }
  }

The view defined is as below where im trying to fetch “option” from JS script please advice

def export_template(request, post):
    #option = int(request.POST.get("option"))
    option = int(request.POST.get("option"))

    if option == 2:
        file = open('C:/Users/Desktop/New Project (2) (1)/New Project/uploadcsv/media/bulk_upload/Update_Client_YYYYMMDD.csv', 'r')
        response = HttpResponse(file, content_type='text/csv')
        response['Content-Disposition'] = 'attachment; filename=Update__YYYYMMDD.csv'
    return response

How to pass JS script value as parameter to my Django view..!`