Good day!

Please excuse me if the question I am asking seems obvious, But I've only recently been learning the theoretical understanding behind SAML 2 Authentication, and with that trying to understand how Okta works. I'm struggling with wrapping my head around how the set up should be for my requirement, What I understand is as follows:

1. My application acts as a SP that initiates Okta SSO from the app that I have created on the dashboard
2. The user signs in successfully that is within my organisation, my app gets the response noting that the login is valid
3. I can redirect the user as I need to

my problem comes into understanding in - I don't want to manually add all the users into my organisation that I want to use my application, I'd like to have some sort of way of letting the user login to their organisations Okta, if its valid login then do the appropriate verification that the user exists in our system, or should be able to access it since our database should have the tenant approval.

Initially I thought that if I add the second organisation as an IDP within the Okta developer dashboard maybe that would be ok. But I think I am missing some information and was hoping someone could help me out here to understand the full picture, and maybe help me by pointing me in the right direction.

Thanks!