@DeppyMetz okay for the first thing, about the chapters, I think it's better to number the chapters, for example : chapter one AND then write the title. For wattpad specifically, I believe that numbering them is better.
Now for the second one, you can try writing something in the notes of your phone, or wattpad as well and then, when you have access to your computer copy the whole thing. An idea might not last for as long as you think and it's bad to know that you've forgotten a good one without having written it down. Of course, you can also use a notebook.
I really hope I helped