A scene is a unit of storytelling. It incorporates all major elements: action, character, setting, inner story, voice, narrative thrust.
If your opening scene is lacking or weak in any of those elements, then your story is in danger of being uninteresting, passive, slow. It just doesn’t grab the reader. Nothing is happening.
The most engaging method these days is to begin in medias res which means “into the middle of things.” The protagonist is not thinking, dreaming, wondering, waiting, eating, ruminating, relaxing, contemplating, etc.
Rather, something is happening to the protagonist (ideally, books these days introduce the protagonist on page one, although it isn’t uncommon to kick off with the antagonist), and the protagonist reacts.