[Django]-New Django app initial DB migrations of an existing database

You want makemigrations to create the migrations. The migrate command applies migrations, it does not create them.

You can use the --fake-initial option so that Django does not try to create the tables that already exist. Note that --fake and --fake-initial are two different commands.

When you run migrate, the django_migrations table is updated to store the currently applied migrations. The migration files themselves are not changed. The --fake command updates the django_migrations table without running the migration. That means that if you use it incorrectly your database and django_migrations table can get out of sync, which can be difficult to fix.