Post-update problems on Galaxy S6 Edge

[AC Question]

I just installed a Android update on my Galaxy S6 edge, prompted by the phone. According to Settings/About device/software info, the phone now post-update has Android ver. 8. So what's wrong? Predictive text has disappeared. To fix this, I keep looking for Languages and Input under settings but can only get there through the search function. Once at Language and Input, there is no Samsung keyboard, where all the tutorial videos say to look to select the predictive text function; there is only Virtual Keyboard and Physical keyboard. So this is the main functional problem for now. Aesthetically the UI post-upgrade leaves much to be desired. The font type on notifications is really not appealing - and is small. But that for another day. Please help me restore predictive text in text message. Thanks.