Your photo is too low-res to see what’s going on.
Though I can’t tell from the murky photo, this is probably not a different network or a neighbor, this is another computer on your same local Wi-Fi, running a file share.
Not unless your connected Wi-Fi is open, or somebody else has your Wi-Fi password.
If you’re running Wi-Fi with WPA2 or WPA3 security with a decent password and haven’t been sharing your credentials around the neighborhood, this is almost certainly another computer on your own network.
A Windows system can show up this way, including the garbage host name.
Network-connected printers and scanners and network-connected storage devices also show up this way, but those usually aren’t named “laptop-whatever”.
If you can’t find it, change your Wi-Fi password. Your Apple devices will all reconnect as soon as one knows the new Wi-Fi password (if iCloud Keychain is enabled), but everything else will have to be reconfigured to rejoin the Wi-Fi.
If this is not on your Wi-Fi network—again, lo-res photo—then it’s another computer network or hotspot somewhere in the area. But from your description, I’m assuming this other computer is on your network. Which means it has your credentials.