How to save list of objects getting from template in django models?

It looks like you are using getlist instead of just get and are sending over simple strings, not lists of items. Based on your form, your view should probably look like this (assuming you have a single field):

def terminer(request,pk):
        get_interv= Intervention.objects.get(id=pk)
        if request.method=='POST' and request.is_ajax():
            equipements = request.POST.get('equipements')
            qte = request.POST.get('qte')
            # do something with equipements and qte

getlist works with form multi-selects and similar objects, like this:

    <select name="equipements" id="equipements" multiple>
{% for equipment in interv.equipements.all %} 
        <option value="{{equipment.id}}">{{equipment.nome}}</option>
{% endfor %}
      </select>

If you need to collect multiple variables for each entry, you could perhaps do it dynamically via JavaScript:

$("#mysubmitbutton").click(function(){
    {% for equipment in interv.equipments.all %}
       var equipment_{{equipment.id}} =  $("#equipment_type_{{equipment.id}}").val();
       var equipment_{{equipment.id}}_qty = $("#equipment_qty_{{equipment.id}}").val();
    {% endfor %}

    var equipments = [
      {% for equipment in interv.equipments.all %}
        { id: equipment_{{equipment.id}}, qty: equipment_{{equipment.id}}_qty,
      {% endfor %}
    ];
    var form_field1 = $("#field1").val();
    var csrfToken = $( "input[name='csrfmiddlewaretoken']");
//collect the rest of the form here
$.ajax({
    ContentType: 'application/json; charset=utf-8',
    dataType: 'json',
    type: 'POST',
    url: '{% url 'Detail_equipement' %}',
    data: { "equipments": equipments, 'form_field1': form_field1, ..., 'csrdmiddlewaretoken':csrftoken, })
               .done(function(data) {
                            if (data.result === true){
                                alert(data.message);
                           }
                       });
});

In your template:

 {% for equipment in interv.equipements.all %}
                  
                                          <div class="col-sm-6">
                                            <div class="form-group">
                                              <label for="modal_signup_firstname">Equipement</label>
                                              <div class="input-group">
                                                  
                                                  <input type="text" id="equipment_type_{{equipment.id}}" name="equipment_type_{{equipment.id}}" value="{{ equipment.nom_equipement }}" class="form-control" placeholder="Equipement" disabled/>
                                              </div>
                                          </div>
</div>
                                      <div class="col-sm-4">
                                          <div class="form-group">
                                              <label for="modal_signup_lastname">QTE</label>
                                              <div class="input-group">
                                                
                                                  <input type="text" id="equipment_{{equipment.id}}_qty" name="equipment_{{equipment.id}}_qty" class="form-control" placeholder="QTE" />
                                              </div>
                                          </div>
                                      </div>
    {% endfor %}

Then, in your view you should be able to use getlist:

def terminer(request,pk):
            get_interv= Intervention.objects.get(id=pk)
            data = {}
            if request.method=='POST' and request.is_ajax():
                equipements = request.POST.getlist('equipments')
                for e in equipements:
                   detail = Detail_equipement.objects.get_or_create(equipements__id=e['id'])
                   detail.QTE = e['qty']
                   detail.save()
             if request.is_ajax():
                return JsonResponse(data)
             else:
                context = {
                'interv':get_interv,
                
                }
                return render(request, 'techniciens/terminer_interv.html',context)

Also, default=True doesn't do anything in a ForeignKey field and you'll need to update your model to this for my code to work (or pass the interventions value in the POST data via ajax):

class Detail_equipement(models.Model):

    equipements=models.ForeignKey(Equipement,on_delete=models.CASCADE)
    interventions=models.ForeignKey(Intervention,on_delete=models.CASCADE, blank=True, null=True)
    QTE = models.IntegerField()

This may need some tweaking, as I can't see the rest of your code to be sure it will work. But hopefully it will get you started.