Hey, it would be good to know what phone you are using. However, predictive text is normally set up automatically. If it is a smartphone you could get a good keyboard from the Google Play Store - Android Keyboard, Swype. And you just set them up to your liking.
Alternatively, try going into settings and there should be an option there to adjust input methods and the like.
Hopefully that helps, but if now, please resubmit your query with further details.
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