The Watched Repositories page allows you to identify the repositories whose changes you want to track.
Click the Add button to add a repository to the Watched Repositories page and to optionally configure Gerrit Code Review to send an email notification whenever a change occurs in that repo.
When adding a repo, use the Browse button to navigate to the repo of interest.
If you want to specify conditions under which you want to be notified of a change (perhaps you are interested only in changes to a specific branch, for example), see the Searching Changes topic in the Gerrit Code Review documentation to learn more about search operations and search expression syntax.