ModuleNotFoundError: No module named 'main.utilities' - but it exists

When I first started this project, I installed bootstrap as it says in my project’s documentation. here is what is written there:

Create a base template
Let’s create the templates directory in the main application package, and the layout directory in it.
This is where the base template of our application will be stored.
To speed up the layout, we use the Bootstrap 4 CSS framework.
use the install command: pip install django-bootstrap4.
Let’s add the bootstrap4 application to the settings.py configuration file:

INSTALLED_APPS = [
...
'bootstrap4',
]

I thought the second option was more correct, most likely I wrote the wrong link somewhere, which points to the correct package. But how is this possible if the project started on the computer at the college and I run exactly the same project but already at home and it doesn’t work here, maybe the error is in something else?

No, it’s more likely a case that you haven’t installed the package at home, while the package is installed at school.

But which package do I need to install?

What do your instructions say? (The ones you copied here.)

What exactly is the moment? When was the bootstrap installed or what exactly?

In message #21 of this topic, you posted a set of instructions.

Those instructions answer your question.