This method will allow flashing a custom recovery or for some phones also Samsung engineering root image.
This method will provide root access to the device.
Odin is the Samsung proprietary alternative to Fastboot.
For the usage of Odin, the phone needs to be in Odin mode. For this, some key combinations need to be pressed, such as Power + Volume Down + Home
This method writes to the system permanently. Need to have an open bootloader, which may cause to delete all data of the device.
Flashing custom recoveries may void your warranty and trip the Knox Warranty void flag!
On the main screen click on "Security Bypassing".
Choose Generic profile.
Select “Connect Odin”.
Follow on-screen instructions.