SAML in Okta is purely carried with the help of user’s agent. So no backend communication will be generated.
I suggest you to have a look at some reference implementation, as SAML is not that simple, and it’s better to grab something pre-built. When I had to deal with the same, I chose ITfoxtec.Identity.Saml2
There are other implementations of SAML frameworks, I’m sure you can find something which fits you better