RE: the Gmail question. (talking about the Gmail web interface on a PC)
Some comments:
1 - the default view for Gmail is Conversation View On - which groups emails with the same subject together.? If you click the Reply button at the bottom of the last message, you are replying to the Conversation and it is quoting/including the prior messages.? ?This just puts the prior emails into the body of the new message you are creating, once there, you can edit the email body as you wish.? Click the 3 dots "..." to expand the quoted text to view/edit it.
2 - when viewing the emails in a conversation, you can expand/collapse individual ones by clicking on the subject.? With an email expanded, there is a "More" menu (3 vertical dots on the right) that gives you options?for that message.? Click Reply in the More menu to reply to that message alone.? It should quote only the content of that message.? Again, this is put in the body of the new email that you can edit as you wish.
3 - Might want to turn Conversation View Off in the Settings to experiment with both views.??
Thanks
Toby