Signing into ChromeIf you log into a Chromebook, you are automatically logged into Chrome; however, if you are working on another computer (like a PC or Mac), you need to log into Chrome to get access to your bookmarks, tabs, and apps. You should only sign into Chrome on a computer that you log into with your username & password. If you sign in on a shared or public computer where you don't log in with your account, the next person who logs in will see your synced bookmarks, apps. etc.
Here are Google's directions for logging into Chrome on a computer (other than a Chromebook):
Once you have signed into Chrome, your bookmarks, extensions, and apps that you have added will "follow" you wherever you go.
As a reminder, this is really designed for computers that you log into with a username & password (or a personal machine). If you're on a shared computer and you aren't logging into it with your credentials, you won't want to sign into Chrome.
Signing in on a Mobile Device
If you're using an Android or iOS device, you can install the Chrome browser for those systems as well and get to your bookmarks. When you launch Chrome, it will ask you to sign in. That will give you access to any bookmarks you've saved, tabs you might have opened on other devices in Chrome, and your history from signed-in devices.
If you want to know more about signing into Chrome (or why you would want to), check out Google's help area.