Using Catalyst for Building saas App

Using Catalyst for Building saas App

I Want To Build an Application to service multi-tenant,
When I read the Documentations of Catalyst API
I found that the Users in Catalyst can have organization_ID and user_ID,
and I can Add multi-users to the same Organization.

Also, I can Set Permissions on Data to get only Records created for that specific Organization

but I don't know how to create Organizations and add these users to it

Please help with an example 

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