First thing to note is that,
Blockly is a frontend part
Django is mainly focused on backend.
You can get the desired outcome by two approaches:
Strategy 1 :
Run a frontend service like react or similar and decoupling the blockly part with Django and make api calls for CRUD service.
Strategy 2 :
Make a static Blockly page in Django using Jinja template and run your scripts.
If your project is heavily dependent on Blockly then, Strategy 1 is recommended , if you just wanted a small part, with less custom blocks then you can go with Strategy 2.
For doubts :
My DISCORD ID : "dev. mmv#4248"