No, I gave a detailed tutorial how to initiate a secret chat and then explained that the procedure has to be done only once per contact. It’s exactly as easy or complicated as I explained. Not more, not less.
It’s hidden away behind a hamburger menu.
No, it’s not. Tap the pencil in the bottom right corner. That’s how I explained it and that’s how it’s done. Hamburger menu is an additional way but the compose button is the pencil in the bottom right corner.