I've read this thread with interest. I'm new to iPhone and I'm amazed that everybody's iPhone seems to be different. It it helps I'll post what I'm doing now. If it doesn't, just click on by ...
I use OneNote for editing and sending mainly standard texts to guests at our holiday let to cover things like breakages and events not mentioned by the instructions on site. One-off texts often find their way into the instructions document. I used Evernote
but was irritated by the constant flow of messages telling me to upgrade or to use more features. Evernote has now been shown the door. The following is what works on my iPhone;
Open OneNote on the phone and get to the paragraph I want to send. Double tap on any word selects that word and brings up the menu. Tap 'select all' and then 'share'. Tap 'messages' (on my phone it's between AirDrop and Outlook) and it brings up the selected
OneNote message as text in the text messages app, leaving me to type part of the recipient's name and then tap the green arrow to send.
Many thanks to all who contributed so helpfully. I'm signing off now until something else gets fouled up.