What are the forms that an international student with the following situation upload in the IDOC?

Non-tax filing parents
Non-tax filing oneself
parents have a business or a farm

The forms section in the IDOC has a combined non-tax filer form while the main page shows that my parents and I need to fill different non-tax filer forms.

It is a little confusing. Any ideas?

You need to contact the financial aid office at the place where you are applying, and ask what they require from students from your country. the Non-tax paperwork is for US applicants who for one reason or another are not required to file US tax returns.