How to render a variable in a Form Field in Django 2.1.7?

Question

Django

I am a beginner jungist using Django 2.7.1 and Python 3.7.2. I'm trying to make a thing that will receive data from Form Fields on the site and process it, and then display the result in another Form Field on the same page.
I tried to solve this whole thing through the methods of the models, but did not understand how to use them, so I decided to try writing functions in views.py.
Also, in the process of searching, I got acquainted with celery and other similar asynchronous solutions, but as it turned out, this will not help me, because I do not understand the essence.
In general, now I seem to be starting to understand, but I don’t understand at all how to render the result on pressing a button with a POST request.
The code is below.
This is models.py

from django.db import models

# Create your models here.

class CombinatorCols(models.Model):
  first_column = models.TextField("Column 1", null=True, blank=True)
  second_column = models.TextField("Column 2", null=True, blank=True)
  third_column = models.TextField("Column 3", null=True, blank=True)
  fourth_column = models.TextField("Column 4", null=True, blank=True)
  result = models.TextField("Result", help_text='Halo', blank=True,)
  def __str__(self):
    return self.first_column

This is my forms.py

from django import forms
from .models import CombinatorCols

class CombinatorForm(forms.ModelForm):
    class Meta:
        model = CombinatorCols
        fields = ('first_column', 'second_column', 'third_column','fourth_column', 'result',)

This is my views.py

from django.shortcuts import render, redirect
from django.http import HttpResponse
from django.template import loader
from .models import Combinate,CombinatorCols
from .forms import CombinatorForm,ResultForm
# Create your views here.


def get_col(request):
  #column = get_object_or_404(CombinatorCols)
  if request.method == "POST":
    form = CombinatorForm(request.POST)
    if form.is_valid():
      column = form.save()
      column.sender = request.user
      first_handle = [i for i in column.first_column.split('\n') if i]
      second_handle = column.second_column
      third_handle = column.third_column
      fourth_handle = column.fourth_column
      column.result = first_handle
      column.save()
      print(first_handle)
      print('Naiiiceee')

  else:
    form = CombinatorForm()

  return render(request, 'index.html', {'form': form})

And finally my index.html:

<form action="" method="post">
  {% csrf_token %}
  {{ form.as_table }}
  <input type="submit" value="Submit">
</form>

I'm expecting the 'results' field on the site to update after the button is clicked and set to the value self_handlefrom views.py, but that doesn't happen. printoutput correctly.