I am using Outlook 2016 and I'm trying to forward meeting invitation to a group of people...When I click on Use form, there are no forms listed and the rule wont let me go past that point.
How do I create a form?
I may not quite understand your question. Which form do you mean?
Normally, you can click Forward under Meeting tab:
If you want to create forms for meetings. I think you can check this TechNet thread: Create Form to pass information
Open a meeting and then choose Developer > Design this form.