All project members can see the hierarchy, but they cannot navigate to other projects, unless they are a member of those projects.
The project hierarchy section is located at the bottom of the project cover page. There can be one parent project, but many child projects.
1- Navigate to any project of your choice.
2- On the button of the project cover page, you can see a section titled Project Hierarchy, as shown below:
3- Click on the “Edit” button to add a parent project and child project(s).
4- Use the two drop menu to select a parent project and any child projects.
5- Once done, simply click “Save”.
It is important to note that users can only see and select the projects that they have access to, and once the hierarchy is set in one project, it will automatically update the other projects in that hierarchy.