The "Sections" tab is actually located under Journal Settings, and allows you to create sections for your journal.
Under the "Submission" tab of Workflow Settings, users can edit the Author Guidelines, Components, the Submission Preparation Checklist, and enable certain Submission Metadata.
The "Review" tab includes the ability to create and edit Review Forms as well as edit Review Deadlines, Automated Email Reminders, Review Guidelines, Reviewer Access, Reviewer Options, and craft a Competing Interests Statement.
The "Publisher Library" tab provides the journal manager with a space to store files relevant to journal upkeep and policy.
The "Emails" tab allows the user to edit the various emails going out to different users, reviewers, and submitters, including the email Signature, Bounce Address, and various Prepared Email Templates.