If you'd like to declutter — or simply hide — specific projects from your Resource Panel, here's how to do it:
How to hide projects in your Resource Panel view
Click on the Projects tab of your lefthand Resource Panel.
Then, click on the Hide / Show Project icon that appears towards the top right corner of the Resource Panel.
After clicking on the Hide / Show Project icon, similar icons will appear next to all of your projects.
Click on the eye icon next to the project(s) you want to hide.
Finally, click on the Hide / Show Projects icon at the top again to finalize your decision.