It is possible for your organization to use a free plan in Airtable, which allows unlimited collaborators on a workspace. As long as your collaborators have Airtable accounts, they can be added to the workspace, even if they are not actively using it. However, some advanced features, revision history, and backups are only available on paid plans.
To create a new workspace with just two collaborators, you can go to your Airtable dashboard and click on the "Create a workspace" button. From there, you can invite your collaborators to the new workspace by entering their email addresses. There is no need to upgrade to a paid plan for this, as Airtable allows you to create multiple workspaces on the free plan.
I hope this answers your question, and please let me know if you have any further inquiries