How can I instantiate multiple models on one user button press (Django)?

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I'm trying to put together a CRM sort of website that allows users to create subjects and have tasks listed under them. These tasks all have a red or green circle under each week based on its completion status for that week.

The problem is I'm not sure how to piece this all together. I can create a task object and have it be listed under the subject but cant find a way to create multiple completion objects and have each one link in with every task and week to allow the user to check off what they completed.

I'd really appreciate if someone could point me in the direction as to how to split up the logic for these models so that I can piece them together. Thank you :D