On a Chromebook, your history, cache, and cookies are found at chrome://settings/clearBrowserData.
Browsing history is the record of what sites you've been to. You usually don't need to clear it.
Cookies are used for login credentials. If a login page is frozen or stuck loading, clear Cookies.
Cache is pre-loaded images from sites you've visited before. If the whole internet is loading slow, clear cache.
Restart your computer each morning to let routine updates through.
When you move physical locations, restart or reconnect to wifi.
Each tab uses bandwidth. If you have more than ten open, close some.
Use the keyboard shortcuts here to speed up your workflow.