You can easily add and remove projects from the Favorites and Recent lists in Project Home.
Add a project to the Favorites list
In Project Home, go to the Recent list and mouse over the project that you want to move to the Favorites list.
Select the Mark favorite icon
.
The project will move to the Favorites list.
Note: A project must be in the Recent list before it can be added to the Favorites list.
Remove a project from the Favorites list
In Project Home, go to the project you want to remove from the Favorites list.
In the project card, select the Control icon
, and then select Remove from favorites.
The project will no longer display in the favorites list.
To add a project to the Recent list
On your default Project Online site, open the project you want to add to Project Home.
The project will automatically be added to the Recent list in Project Home.
Remove a project from the Recent list
In Project Home, go to the Recent list and mouse over the project that you want to remove.
Select the Control icon
, and then select Remove from list.
The project will no longer display in the Recent list.
Source: Microsoft