Accessing multiple APIs each with its authorization server


I am looking for an approach to create a portal that aggregates multiple APIs. The user authenticates once with the portal, and is shown a set of API (functionality) that they have access to. When they access any of these APIs / apps, they need to be granted access seamlessly. Each API / app may have their own IdP. APIs will be onboarded to the portal before they are used, so trust can be established between the portal and these APIs, etc.

What is the approach that is typical for this kind of scenario? Is there a way in which the portal can ‘exchange’ the user’s access token (that they obtained to access the portal itself) for an access token specific to each API / app?

Thanks in advance!