Hi @Abdullah El Tahawy ,
I tested in my environment and the situation is the same as yours.
When I use "Edit in grid view" it is like this, but also make date and time selection separately.
In my opinion, it is by design.
Could you please provide me a screenshot of the other list you mentioned? Maybe it used custom code, please check.
Update on 5/3/2023
Regarding the video you provided, I followed his steps to create a Microsoft List using the same template, but, unfortunately, the actual effect is not the same as in the video. When I click to start editing, he will become two parts.
This is an upgrade of the product, and all newly created lists should work in this way.
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