HI nikhilj8904,
Please share the exact system model no of the laptop.
The Service Tag is located at the bottom panel of the laptop on a bar-code.
Alternatively, you can access the Service tag information by going to the BIOS screen. Power off the computer -> restart the computer, tap F2 on the Dell logo -> Once you are on the BIOS screen, the Service tag will be on the main page (may vary depending on system model and BIOS page).
You may provide the hardware ID so that I can look for the driver. Expand Other Devices, right click on Network Controller/Ethernet Controller -> choose Properties -> Details -> from the drop-down under properties, choose Hardware ID.
Please reply if you have any questions.