Is there a way to run the sound of Pc and Xbox over a loudspeaker?

I want to buy a new monitor for my Xbox. So I would have 2 monitors, an Xbox, a PC and speakers. Since most monitors do not have built-in speakers, would I have to buy speakers again or? Is there a way to get the sound with a speaker from both the Xbox and the PC?

I'm happy about helpful answers.

It's called 1 monitor & 2 monitors

Thanks, but that did not answer the question. "It" is capitalized in your case. So not helpful.

I only know that it goes with a mixer