It can be done in three simple steps easily and it will help you to decide whether you can get the user input through buttons or through the keyboard.
Follow these steps to know how to enable/disable message composer on your Messenger chat flow.
Step 1: Go to the flow in which you have to use this feature,
Step 2: Click the “Action” >> Messenger >> “Enable Message Composer/Disable Message Composer” on the list.
Step 3: That’s it
Like we said before, it can be done in 3 simple steps