
Some actions — submitting an expense, sending a request, deleting a record — shouldn't happen on a single click. A Modal pauses the flow with a focused summary of exactly what's about to happen, so the user can double-check the details before confirming.
Attach an "Open Modal" action to a button. In this expense form, the Review & Submit button opens a confirmation modal instead of submitting immediately.
Fill the modal with the real details of the action — not a generic "Are you sure?". Here, the modal shows the actual amount, expense description, date, department, and the manager who will review it, all pulled from the fields the user just filled in.

The user confirms or backs out. Clicking Confirm & Send completes the action; closing the modal returns them to the form with nothing submitted.
The user gets one last, specific look at what they're about to do — reducing accidental submissions and giving them confidence the right thing is about to happen.