Check the sticker on the bottom of the laptop
Check inside the battery compartment if the battery is removable
Check the original box or purchase receipt
Open Command Prompt and run `wmic bios get serialnumber`
Open PowerShell and run `Get-CimInstance Win32_BIOS | Select-Object SerialNumber`
Open System Information and look for the BIOS serial number
Check the BIOS or UEFI setup screen
Use the manufacturer’s support app or website
Check the laptop’s settings or device information page
Contact the manufacturer’s support with your device details