So my programmer set up the portal on my site. I test it and it doesn't accept my credentials from my site :/ Why?
I see that you've created a ticket (#62663) reporting this issue. The screenshot that you shared shows the customer portal login page asking for the credentials. When SSO is setup, the customer portal URL will be disabled and it would give you an error saying "Sorry, we couldn't find that page". It wouldn't ask for the credentials at all. SSO allows you to use the authentication of your site to access Chargebee's customer portal.
A portal session has to be created for the customer and they'll be redirected to the customer portal without having the necessity to login.
I just cross-checked the database and see that SSO is enabled now. Are you still facing issues?