Send OneSignal push to particular users

How do I send OneSignal push notification to some particular users when some page is open?
When a transaction is done, the app will go to a “ThankYouPage”, I need when this this page is shown, OneSignal will send a push to some particular users with some fixed content.

Someone help, thanks in advance.

Login to your one signal account.If you are connected your app with appId, googleProjectNumber as well as created a firebase app (In case you are using FCM) you can generate new push from the dashboard inside messages,there you can select a particular user you want to send notification message.

Sorry, what you mean is to that inside OneSignal platform. But I need to code this inside the ionic project.
When “thankyoupage” is opened, it trigger a function to send some fixed content to some particular users.
Is that possible? Thank you.

Push notification is generated using FCM(firebase cloud messaging).From one signal dashboard you can select a particular user or a group of people you want to send push notification.

hi, thank you, will try.