To access Timesheet service settings, go to
Settings (gear icon on the top-right corner)
> View All > Timesheet (Visible only to Super Administrator and roles with administrative access).

Additional tabs include:
Extend Service: This tab features adding and editing custom forms and custom buttons. These features extend the default capabilities of the Timesheet service to match the requirements of different organizations.
Approvals: Setup an approval flow for processes initiated from the Timesheet service.
Automation: Manage Timesheet schedulers, and reminders, create automated processes (workflows), create custom notifications such as email alerts, set up templates, and more.