Hi Rod,
Thank you for posting your problem i am here to assist you. May i know the model of your Surface. All Surface models has a built in speakers as they are a fundamental feature for audio output and communication.
To try check click the icon of the speaker on the system tray near the date and time. You can adjust the volume then try to play any sounds from the Web.
If speaker icon is not available you need to update your Audio driver. Click start button search settings and open. Choose Systems then select Sounds. Then click on Troubleshoot common sound problems.
if this won't work try next step.
Click start button search settings and open. Choose Systems Update and click check for updates.
for more details you can check this article from Microsoft:
https://support.microsoft.com/en-us/windows/fix-sound-or-audio-problems-in-windows-73025246-b61c-40…
looking forward to helping you out. If you need more help please feel free to let me know.
Best regards,
Jansher