How to edit a model?

I've created a model which I like to adjust now.

Here:

the docs refer to a "down arrow" - but I can't find this.
Where is it?

Additionally, I can see a small exclemation mark:
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What does this mean? (There isn't more info / hover info)

click on the 3 dots on the upper right side of the page: edit query definition or edit metadata
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