I don't know the exact steps, but go into the Settings>Keyboard settings and look for anything that is enabled that says T9. May also be referred to as 3x4 keyboard. Disable it.
Welcome to Android Central! Go to Settings>General Management>Samsung Keyboard Settings>Languages and Types, then tap English. Make sure it's set to Qwerty and not 3x4
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Can also reset your keyboard by going settings>apps>scroll down the app list until u find your keyboard then tap >storage clear data then force stop it this should reset the keyboard