The only permanent and secure way to unlock a device is through Apple's official channels. This process does not require downloading third-party software but involves formal documentation.
Remove a device from Find Devices on iCloud.com - Apple Support (IN) download-icloud-unlock
You must provide the device IMEI or serial number. The only permanent and secure way to unlock
You can initiate an Activation Lock Support Request with Apple if you have the original proof of purchase. download-icloud-unlock
For managed devices, organizations can use a bypass code generated by their management server. 2. Legitimate Remote Unlocking