Hi Clarisse! Thanks for asking! I hope it’s OK that I answer in English?
You asked: “Hello, I would like to know how to copy, paste a layer and then draw on the new layers without it drawing on all the layers. Thanks”
Maybe it’s the translation (Google) – but I don’t think you mean “layer” – you mean “drawing” or “frame”, right?
In Animation Paper, you can easily make a drawing “hold”, by just dragging down on it in the X-Sheet. Then you will see a number of “clones” after the original drawing. These will automatically update if you draw on them or the original.
You can brake the link by hitting O on a clone (Making the clone an original). Then you can continue drawing without the previous drawing being updated.
If you Clear a clone (hit * on it), you will break the link too, and make it an original blank drawing.
You can also do copy/paste, by using Ctrl C and Ctrl V on the thumbnails (drawings) in the X-Sheet.
But instead of copying and modifying your previous drawing, I would recommend adding a new blank and then use the light table (onion skin), to draw the new drawing, referencing the previous one. But it’s up to you of course and up to what is best according to the project and style.
Anyway, good luck with it! Let me know if you need me to go into more detail or if you have other great questions!