Firebase Admin - Send Push Notifications

I'm trying to create a basic website which allows the user to send a push notification using FCM.

The website holds a form where you select a device token, and enter text for a message body.

I think I need to hook this up to Firebase-Admin but i'm not sure how to go about it. Is Firebase-admin what I need to make the project work?

I've managed to connect this to my database using standard Firebase connections to retrieve a list of the device tokens registered.