What should I display when the user commit an action?

I'm trying to develop JavaFx application. I'm a beginner in UX and I'm confused between what I need to do for notify the user that the operation are commited correctly.

I have a form that contains the information of an employee when the user writes the information and clicks Save. He then receives a push notification.

I'm confused if I should display a push notification or an alert or any of these?