Multiple GraphQL Services

Hi, I’m researching how I could merge multiple graphql apis under one graphql.
I have been reading about apollo gateway which seems more simplistic, but since it’s being deprecated I think I should use the new system. But I’m confused since if I understand it correctly in gateway you could declare the source of the service and then the gateway created one schema from multiple sources. But I don’t know how you do it in the new system. Also, I need to mention that I don’t have much of an option to modify API schemas since they are generated based on code.

After some research, I found out that it’s possible to generate a super-graph which is needed for the router via URL through the rover. Which is exactly what I needed.