How to insert a note between two other notes and how to change the length of a note in an existing score?

Thank you for answering me. As you ask, I give you more information.

Maybe I didn't make myself clear. I'll give you an example in the attached mscz file. In measure 2, I would like to insert an E between the D and the F. If I click on the note F and I put myself in note insertion mode by pressing the N key. If I now type an E, this E will replace the F, but that's not what I want. I would like to insert an E between D and F and push all the following notes. You tell me that inserting a note could only cause me harm and that it's better to rewrite. But that would mean that to add a single note to the second measure, I would have to rewrite the whole score!!! I'm sure there must be an easier way!

Pleas have the text of your question give us mor information than the title.
Inserting a note will only cause you grief. Rewrite instead.
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