class ProjectRating(models.Model):
    rating_user = models.ForeignKey(User, on_delete=models.CASCADE)
    rating_project = models.ForeignKey(Project, on_delete=models.CASCADE)
    project_owner = models.ForeignKey(Project.project_owner,on_delete=models.CASCADE)# проблема здесь
    project_relevance = models.IntegerField(validators=[validate_int])
    project_feasibility = models.IntegerField(validators=[validate_int])
    project_originality = models.IntegerField(validators=[validate_int])
    project_elaborate = models.IntegerField(validators=[validate_int])
    project_report_quality = models.IntegerField(validators=[validate_int])

class ProjectRating(models.Model):
    rating_user = models.ForeignKey(User, on_delete=models.CASCADE)
    rating_project = models.ForeignKey(Project, on_delete=models.CASCADE)
    project_owner = models.ForeignKey(Project.project_owner,on_delete=models.CASCADE)# проблема здесь
    project_relevance = models.IntegerField(validators=[validate_int])
    project_feasibility = models.IntegerField(validators=[validate_int])
    project_originality = models.IntegerField(validators=[validate_int])
    project_elaborate = models.IntegerField(validators=[validate_int])
    project_report_quality = models.IntegerField(validators=[validate_int])

@register.filter
def index(list_, pos):
    if pos <= len(list_):  # или через try
        return list[pos]
    return ''

{% for field in form %}
  
  {% if not field.is_hidden %}
    <p>{{ questions|index:forloop.counter0 }}</p>
    <p>{{ field }}</p> 

  {% else %}
    <p>{{ field }}</p> 
  {% endif %}

{% endfor %}