New iPhone 7 isn't learning my words

I purchased my new iPhone 7 red (Special Edition) in May 2017 and it still has not learned any of my words plus autocorrect changes all my words. I see that I type them correctly but it immediately changes them. Example: I put "into" in the sentence and 2 times it changed it to "intermediate" and the 3rd time to "indexes". Many times it doesn't offer a better word, such as "nsme" did not give me "name" as an option. Simple misspelled words have no options to replace. Is there a fix coming for this?