Here's how to export a PNG of any frame in an artboard, directly from the editor:
Select the point in the Timeline that you'd like to export
Right-click on the artboard
Select Copy as > Copy as PNG or Download as PNG from the menu
The image will copy to your clipboard or download instantly to your device
This also works across multiple artboards at once: just select them all before right-clicking.
If you need a frame-by-frame export rather than a single still, check out our article on exporting a PNG sequence, which is available on the Max plan.