Screen recording laptop?

I'd like to record a phone call with someone, but I want their voice to be heard too. On a mobile phone, when recording, you neither hear my voice nor your voice and only have the video without sound.

During the phone call I will speak without headphones.

Do the system sounds or speakers / headphones have to be at 100% and can I then switch the other to 0%?

Hopefully your interlocutor agrees?

Of course, otherwise I wouldn't ask 😌