Network connection was lost during upgrade

Hi Ramirezdiana,

If we understand correctly, your Mac is missing your preferred network connection after installing macOS Big Sur. When you have a chance, check out the resource we've included below, which will walk you through adding a new network location.

How to use network locations on your Mac

If we've misunderstood your original question in any way, please feel free to provide additional details and we'll keep working from there.

Have a great day!