Hi. Can you provide some more details, please? What do you mean by "interacted with" and "not accessible"? I'm not sure what you're expecting to happen. The project dependency nodes in the Solution Explorer view can be right clicked, and you can view properties, delete, find dependent code, navigate to the actual project in Solution Explorer and so on. You can also right click on the Projects node itself and add more project references.

However, please note that generated projects are not expected to be edited by users, as the next time something changes in Unity, the project files will be regenerated and any changes will be overwritten. So any changes made - adding or deleting a reference, for example - will be lost with the next change made in Unity.