If you've been given access to do so, you can view other colleagues in Sage HR. Depending on settings, you may also be able to clock on them to see further details for them.
On the main menu, click Company.
To view a colleague's details, including their email address if an admin has made this possible, simply click on the relevant employee to see their employee info card.
If you are an admin user or a manager you'll be taken to the employee's profile when you clock on them.