This article offers several solutions if your Chromebook is running slower:
9 Ways to Speed Up Your Chromebook
One of the easiest ways to figure out how to speed up your Chromebook is to check out the Task Manager on your Chromebook.
To open Task Manager, open Chrome, select the three dots at the top right, then select More tools > Task Manager.
In the Task Manager window, you can see which apps are using the most CPU or memory on your Chromebook. If you see any culprit apps here, uninstall them to free up your Chromebook's resources and improve its performance.
