I think I can help with the Cell usage issue.
You may in fact have cell data turned on, but it may be turned off for specific apps.
Please go to Settings...Cellular.
First, ensure that Cellular Data is turned on.
Next, scroll down the page and you should see a list of all your apps.
Make sure Cell data is turned on for the apps in question.
Lets get you the help needed! What happens when you attempt to send a text message? ( any error messages) How long has this been occurring?
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