Step 1: The first step is to open Your GMail Inbox and click Settings

Step 1 image

Step 2: Click Settings

Step 2 image

Step 3: Click Writing suggestions off

Step 3 image

Step 4: Click Save Changes

Step 4 image

Step 5: That's it. You're done.

Step 5 image

Here's an interactive tutorial for the visual learners

https://www.iorad.com/player/146725/GMail--Disabling-Smart-Compose