Fully Disable autocomplete on a Macbook?

[ParallelLimes]

I am typing this on my MacBook in Safari. I recently updated to Tahoe 26.2. I am at the end of my tether. The bloody thing now tries to "guess" what I want to type. I can't stand it. First a suggestion appears in grey, then, if I finish a word before the "grey" bit disappears and press the space bar, it changes my word to the bloody word it thinks I wanted. For example if I type "exam" and it thinks I want "example", I press space at the end of "exam" and it just changes it to example. I've tried turning off the spelling/grammar options in the edit menu on Safari but it's made no difference. It also does it on my Apple Notes. There seems to be no quick fix on the Apple forums. Does anyone techie know how to make this stop please? Text replacement is not checked in the substitutions menu! Similarly, MS Word is doing it but only in the comment notes when I comment on texts (not in the main document) with no way seemingly to disable it. Is it all connected?

To stop word prediction in Safari (on iPhone/iPad), go to Settings > General > Keyboard and turn off "Predictive,"

For Mac, System Settings > Keyboard > Text Input > Edit, and disable "Show inline predictive text," which stops suggestions as you type.

To turn off predictive text in MS Word comments, you need to disable the "Text Predictions" feature in Word's settings (File > Options > Advanced > Editing Options > uncheck "Show text predictions while typing") and also check your Windows settings for typing suggestions.

OMG thank you! Just done this on my Mac and it's fixed it! (It was Safari on the MacBook doing it, not on iPhone).
The MS Word thing, I've already got all MS Word autocorrect/text predictions fully disabled (which I think is why it's not doing it in the main document). Now I know it was a global settings issue not an in-app issue, I suspect the Mac keyboard settings have been overriding the MS Word inline comments setup.

Or if you don't want the suggested text, press the esc key