Approver for a change?

Approver for a change?

Hi, I am new to the Servicedesk Plus and I am configuring the change management workflow.  I see there are two places that I can input an approver for a change.  The first one is when I create a new change, I can add approver at the bottom of the submission page.  The second one is inside the workflow, I can add an approval block and then designated the approvers in the block.  I am a bit confused about this as why there are two places to set approver for a change and which one should I use?

                  New to ADSelfService Plus?