Editing an item is the same form you filled when you created it. What is worth knowing is how saving behaves.
Saving is per item, not per field
Fields commit together when you save the item, so a half-finished edit is not visible to anyone until you are done. Leaving a field empty is fine; it does not block the save.
What to reuse
Troubleshooting
My edit did not appear in the shop
Saving stores the change in Content Hub. Reaching a shop is a separate step that depends on the integration and when it next runs.