This option is asking what type of sign-in flows do you support. You can choose either IdP or SP initiated, or both.
If you do not have IDP flow, you may not need to select it.
Hi, Sorry for the slow reply. My understanding is that the app will show up on the end user’s app dashboard but unfortunately nothing will happen when it’s clicked on because IdP initiated flow is not supported. So supporting this option provides the better experience and makes it easier for customers to access your app.