imessage

Hi guys, So recently i converted all my text messages on my iPhone to a PDF file. The document is over 5000 pages long. I've been looking for ways to see how many individual texts there are in the document. I'll upload a screenshot so you guys can have a rough idea what it looks like. Is there...

All the tutorials I've read, including the one here, make it sound like you can give any group chat a name. It seems, though none of them mention it, that this only works if every member of the group is using an ios device. Is that your understanding?