Why There is No Animate Editing Mode in Exported Canvas?

I exported a grouped layers to a new canvas. From all of the tutorials that I’ve seen on the internet, we can modify the canvas, such as add new keyframes, without affecting the keyframes in main canvas to make an independent moving object. And the green man was there.

But I have no green man in my exported canvas. How could I edit or add any keyframe on it if there is no animate editing mode button.
I tried to edit the path of a shape on the exported canvas and then appeared a notification such as “are you sure you want to modify the object while not in animate editing mode”.
and yeah, I cannot make it in animate editing mode.

So how could I edit the exported canvas, specifically to add the keyframes.

Please help me.
Thank you.