As an Admin, you can setup a hierarchical approval flow by following the steps given below:
Submits to: You can assign a default approver for the new user. All the reports from your new user will be sent to the user selected from Submits to drop-down.
If you choose the user role as Approver, or Admin, you will see an additional field:
Approves and forwards to: You can set another level of approval for this user. So, all the reports that are submitted to this user will be forwarded to the selected approver, whose name was chosen from the Approves and forward to drop-down.
Clicking the + add criterion option will allow you to set a criteria based on which the submitted reports will be forwarded to the next approver.