@Erik Verheuvel It is still available.
Azure event grid is a service that connects data sources and event handlers.
Azure Event Grid allows you to easily build applications with event-based architectures. First, select the Azure resource you would like to subscribe to, and then give the event handler or WebHook endpoint to send the event to. Event Grid has built-in support for events coming from Azure services, like storage blobs and resource groups. Event Grid also has support for your own events, using custom topics.
Check this
If you are doing it for the first time, could you please confirm if you have registered "Microsoft.EventGrid" provider?
You may also follow custom-event-quickstart-portal for the event grid quick start.
Please let me know if this helps.