Configure rules for target branches

I am using a Premium Cloud Gitlab. I cannot find this option.
Documentation says:
To create a target branch rule:

  1. On the left sidebar, select Search or go to and find your project.
  2. Select Settings > Merge requests.
  3. Select Add target branch rule.
  4. For Rule name, provide a string or wild card to compare against branch names.
  5. Select the Target branch to use when the branch name matches the Rule name.
  6. Select Save.