I am trying to book Copa flight on my return leg but want to create a 2 day Copa Stopover on my way to EWR

Is a stopover something that the airline reservations creates or do I create within my booking?

Example
BOG - PTY - EWR (copa airlines reservations allows me to stay two days in PTY before proceeding to EWR

or

BOG - PTY (ticket one)
PTY - EWR (ticket two / two days later)

Thanks for any assistance