Set insert length

I am new to Cubase and I am trying to familiarize myself with key commands.
One category that I don’t understand is “set insert length.”
It sounds self-explanatory but I can’t find anything in the manual about where I would use it.
I see: Edit> range> insert silence.
But that’s it. Maybe I’m just over looking something.
If anyone can enlighten me as to where and how these set insert length shortcuts can be used, I would be most grateful.

It determines the length of the note when drawing notes in with the mouse.

Insert Silence will add bars (or silence) into your project. You use the locators to tell it where and how much to add. If there is anything in the project after the locators, it will be moved to make room for the silence.

Oh, that makes sense. Thank you.