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.