Ideas to include
How it started
The night you met, the friend who introduced you, the first trip. The song needs a beginning so that the question at the end feels earned rather than dropped in.
The question at the end
Tell us the exact words you want, and whether the song builds to them or arrives at them quietly. That final line is the one to get right, so you approve it first.
The scene you are planning
The beach, the kitchen, the hotel room, the family waiting in the next room. Tell us the setting and we shape the length and the mood to fit that moment.