Need to find a complete list of google text app settings and options

[Robert Zwilling]

Does anyone know of where to find a complete listing of all the options and settings for google text app listed in a single place, such as a very complete instruction manual.
Somehow the words for all the text messages are not being shown, only the images are there. Almost like a setting was tripped that said show images only or hide all text. Messages coming in are not showing the text, though the preview of the text message can be seen. delete cache doesn't fix the situation.