Call External Number while another call is on hold

Hello;

We are using CCP to handle calls in aws connect. When an agent gets a call, sometimes s/he needs some more information. And gets the call on-hold. And wants to make a call to external number. When s/he clicks Number pad, s/he can see numbers, but there is no call button. Only End call button. Agent can make a call to quick connect. But it is not always best solution as we cannot record every number as quick connect.

Is there any way to call external numbers without registering them as quick connect first?

Thank you..