Azure NotificationHubs how do I get the devicetoken from an iPhone - apple-push-notifications

Question

I am using Azure NotificationsHubs for iOS push notifications and want to get the deviceToken to register the device, along with the user, in a table through an api so I can send notifications to specific users/devices and keep track of badge counts. When not using Azure Notification Hubs.
func application(
_ application: UIApplication,
didRegisterForRemoteNotificationsWithDeviceToken deviceToken: Data
) {
print("DeviceToken: \(deviceToken)")
}
I see the documentation says:
By default, the SDK will swizzle methods to automatically intercept
calls to UIApplicationDelegate/NSApplicationDelegate for calls to
registering and intercepting push notifications, as well as
UNUserNotificationCenterDelegate methods. Note this is only available
for iOS, watchOS, and Mac Catalyst. This is not supported on macOS and
tvOS.
I'm not sure what swizzling means but I don't want to disable what I have working thus far. Is there another way within the standard implementation to get the deviceToken?
I also see this in the documentation:
To target a particular user on the backend, you can specify a tag such as $UserId:{VALUE} where VALUE is the user name you have specified, just as you can target an installation using the $InstallationId:{VALUE} tag.
But how do I get the InstallationId and is that different from the deviceId or value I use in xcrun simctl push? I expect somewhere I will need to store it on the server side and associate it with a user or something.
I read this post which states:
When you send a notification from the server, one of the paramters is the device ID.
I could do it by user only, but what if they want different notification preference for different devices?
I expect to send to a specific user on a specific device from the server you would use tags, for example:
Microsoft.Azure.NotificationHubs.NotificationOutcome outcome = null;
String userTag = "(UserId:xxxx)";
// substituting for iOS
var toast = "{\"aps\":{\"alert\":\"This is a test\"}}";
outcome = await Notifications.Instance.Hub.SendWindowsNativeNotificationAsync(toast, userTag);
On the client, I am setting the user id like this:
let userId = "xxxx"
MSNotificationHub.setUserId(userId);
Even without the device id part of it, I can't get the user part working. I can send a notification without any tags, but I add in the user tag and it does not work. I assumed by calling setUserId that would add a tag, based on the links above.