models.py

from django.db import models

class Categoria(models.Model):
    nome = models.CharField(max_length=100)

class Produtos(models.Model):
    prod_nome = models.CharField(max_length=250)
    qtd_estoque= models.IntegerField()
    preco = models.DecimalField(max_digits=8, decimal_places=2)
    categoria = models.ForeignKey(Categoria, on_delete=models.CASCADE, default=None)

urls.py

from django.conf.urls import url,include
from django.contrib import admin

urlpatterns = [
    url('admin/', admin.site.urls),
    url('estoque/', include('ml_estoque.urls')),
]

views.py

from rest_framework.views import  APIView
from rest_framework import status
from rest_framework.response import Response
from ml_estoque.models import Produtos
from ml_estoque.serializers import EstoqueSerializer
from rest_framework.exceptions import NotFound

class EstoqueList_create(APIView):

    def get(self, request):    
        estoque = Produtos.objects.all()
        serializer = EstoqueSerializer(estoque, many=True)
        return Response(serializer.data)

    def post(self, request):
        serializer = EstoqueSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
    
class EstoqueList_ChangeAndDelete(APIView):

    def get_objects(self, pk):
        try:
            return Produtos.objects.get(pk=pk)
        except Produtos.DoesNotExist:
            raise NotFound()

    def get(self, request, pk):
        Produtos = self.get_objects(pk)
        serializer = EstoqueSerializer(Produtos)
        return Response(serializer.data)
    
    def put(self, request, pk):
        Produtos = self.get_objects(pk)
        serializer = EstoqueSerializer(Produtos, data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)
    
    def delete(self, request, pk):
        Produtos = self.get_objects(pk)
        Produtos.delete()
        return Response(status=status.HTTP_204_NO_CONTENT)

class CategoriaList(APIView):
    def post(self, request):
        serializer = CategoriaProdSerializer(data=request.data)
        if serializer.is_valid():
            serializer.save()
            return Response(serializer.data, status=status.HTTP_201_CREATED)
        return Response(serializer.errors, status=status.HTTP_400_BAD_REQUEST)