To open bootloader (fastboot) mode on a Nokia 1.4 (likely what you mean by Nokia 14), you can use a hardware button combination or ADB commands from a computer. Method 1: Hardware Button Combination
: When the screen turns on or you see the Android logo, let go of the but keep holding the Volume Down how to open bootloader mode on nokia 14
For safety: Do not attempt to flash or unlock unless you have the correct firmware backup. Always confirm your exact model by going to Settings → About phone → Model number. To open bootloader (fastboot) mode on a Nokia 1
This is the most direct way to enter the mode without a computer. your Nokia 1.4 completely. Press and hold the Volume Down buttons simultaneously. As soon as the screen turns on, release the Power button but keep holding Volume Down until the Bootloader menu appears on the screen. Open the Settings app on your Nokia phone
Activation: Continue holding until the device vibrates or the screen turns on. On the Nokia 1.4, you may see a screen that reads "Download mode" or a black screen with "fastboot" text.
Therefore, while you can enter bootloader mode on a Nokia 14 (if it exists), you cannot unlock it for custom software installation unless the device is an older model or a developer edition—neither of which applies to a budget Nokia 14.