Q:

Unable to get data of Foreign key tables in same serializer

Order table
class Orders(models. Model):
    restaurant = models. ForeignKey(Restaurant, on_delete=models. CASCADE, blank=True, null=True)
    tableid=models. IntegerField()
    orderid=models. IntegerField()
    total_amount = models. DecimalField(max_digits=10, decimal_places=2)

Articles table to save articles like pizza
class OrderArticle(models. Model):
    order = models. ForeignKey(Orders, on_delete=models. CASCADE)
    article = models. ForeignKey(Articles, on_delete=models. CASCADE)
    # article_options = models. ManyToManyField(ArticlesOptions)

Article options to save extra topping or any option available 
class OrderArticleOptions(models. Model):
    # order = models. ForeignKey(Orders, on_delete=models. CASCADE)
    article_option = models. ForeignKey(ArticlesOptions, on_delete=models. CASCADE)
    order_article = models. ForeignKey(OrderArticle, on_delete=models. CASCADE)
    quantity = models. IntegerField(default=1)
    price = models. DecimalField(max_digits=10, decimal_places=2)

EDIT
Article Option table 
class ArticlesOptions(models. Model):
    articleoptionrestaurant = models. ForeignKey(Restaurant, on_delete=models. CASCADE , blank=True, null=True)
    optionname = models. ForeignKey(ArticlesOptionsName, on_delete=models. CASCADE, related_name="optionnames")
    min = models. IntegerField()
    max = models. IntegerField()
    choice_price = models. DecimalField(max_digits=10, decimal_places=2)
    choice = models. CharField(max_length=255)
    def __str__(self):
        return str(self.optionname)

So Now issue is When I try to get all data in one serialize I am not able to get .  I am using this example to get
https://www.django-rest-framework.org/api-guide/relations/
EDIT
My serilizers are
class OrderSerializer(serializers. ModelSerializer):
    restaurant=RestaurantSerializer(required=False)
    class Meta:
        model = Orders
        fields = ['restaurant','tableid', 'orderid', 'total_amount']

class ArticlesSerializer(serializers. ModelSerializer):
    order = OrderSerializer(read_only=True)
    article=ListArticleSerializer(read_only=True)

    class Meta:
        model = OrderArticle
        fields = ['order', 'article']

class ArticlesOptionSerializer(serializers. ModelSerializer):
    article_option = ListCategoriesSerializer(  read_only=True)
    order_article=ArticlesSerializer(read_only=True)

    class Meta:
        model = OrderArticleOptions
        fields = ['article_option','order_article','quantity','price']
    depth=1

My view.py is 
class OrderedArticles(APIView):
    def get(self, request, restid):

        Options=OrderArticleOptions.objects.filter(order_article=1)
        orderserlizer=ArticlesOptionSerializer(Options , many=True)
        return Response(success_response({'orders': orderserlizer.data},
                                         "Restaurant with this all data."),  status=status. HTTP_200_OK)

My JSON Response is 
   "article_option":{  },
        "order_article":{  
           "order":{  
              "restaurant":{  },
              "tableid":12,
              "orderid":1,
              "total_amount":"0.00"
           },
           "article":{  
              "id":1,
              "category":{  },
              "ingredient":[  ],
              "articleoptionnames":{  },
              "restaurant":{  },
              "articlename":"Article1",
              "price":"1.90",
              "pickuptax":6,
              "dineintax":21,
              "description":"This is a tekst field with more information about the product",
              "image":"/media/Article/c1.264f3b28_sxcPiqi.png"
           }
        },

While I want these "article_option" to be as  child of article like   Article {article_option1, article_option2} but its creating new objects with every new article option. 

A:

If I understand you correctly, you want to return a representation of OrderArticle which have ArticleOption objects as its children.  Which means you should instantiate an ArticlesSerializer in your view, but also modify ArticlesSerializer so that it includes all related article_options as a list (using the source attribute).  Something like the following:
class ArticlesOptionSerializer(serializers. ModelSerializer):
    article_option = ListCategoriesSerializer(read_only=True)

    class Meta:
        model = OrderArticleOptions
        fields = ['article_option', 'order_article', 'quantity', 'price']

class ArticlesSerializer(serializers. ModelSerializer):
    order = OrderSerializer(read_only=True)
    article = ListArticleSerializer(read_only=True)
    article_options = ArticlesOptionSerializer(read_only=True, source='orderarticleoptions_set', many=True)

    class Meta:
        model = OrderArticle
        fields = ['order', 'article', 'article_options']

Then in your view, you should instantiate your ArticlesSerializer with the appropriate OrderArticle object: 
class OrderedArticles(APIView):
    def get(self, request, restid):
        order_article = OrderArticle.objects.get(pk=1) # get pk/id from request
        serializer = ArticlesSerializer(order_article)
        return Response(serializer.data, status=status. HTTP_200_OK)

