Hi feroza mohmed,
Thank you for reaching Microsoft Community. I'm sorry to hear that your Surface Laptop 3 is unable to connect to the internet after an update.
You mentioned that the device keeps on showing Airplane mode, what happens if you try to turn off Airplane mode?
Also, when you go to Windows Setting > Network and Internet, does the Wi-Fi option shows up or not?
May I know which Surface Laptop 3 configuration do you have? AMD or Intel?
Lastly, when you go to Device Manager, expand Network adapters, does the Intel(R) Wi-Fi 6 AX201 160MHz (for Intel) or Qualcomm Atheros QCA61 Wireless Network Adapter (for AMD) shows up or not? If not, try clicking Action > Show hidden devices then see if the adapter mentioned shows up.
Try also to boot the device to its UEFI screen by following the steps provided here: How to use Surface UEFI - Microsoft Support. Once you are on the UEFI page, go to Devices tab then see if the Wi-Fi option is enabled. Enable the option if not enabled but if the option is already enabled, disable it first then select Exit > Restart now. After the restart, boot back to the UEFI page and enable the Wi-Fi option back then see if issue persists.
Let me know how it goes.
Kind regards,
Marrion