Follow the step: 
1. Import UserNotifications.framework and go to your AppDelegate class.
In .h
#import <UserNotifications/UserNotifications.h>
@interface AppDelegate : UIResponder          <UIApplicationDelegate,UNUserNotificationCenterDelegate>
@end
- Register for push :  - #define SYSTEM_VERSION_GRATERTHAN_OR_EQUALTO(v)  ([[[UIDevice currentDevice] systemVersion] compare:v options:NSNumericSearch] != NSOrderedAscending) 
 
Now add this in did finish launching :
-(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{
   [self registerForRemoteNotifications];
return YES;
}
 - (void)registerForRemoteNotifications {
  if(SYSTEM_VERSION_GRATERTHAN_OR_EQUALTO(@"10.0")){
    UNUserNotificationCenter *center = [UNUserNotificationCenter currentNotificationCenter];
    center.delegate = self;
    [center requestAuthorizationWithOptions:(UNAuthorizationOptionSound | UNAuthorizationOptionAlert | UNAuthorizationOptionBadge) completionHandler:^(BOOL granted, NSError * _Nullable error){
         if(!error){
             [[UIApplication sharedApplication] registerForRemoteNotifications];
         }
     }];  
}
else {
    // Code for old versions
}
}
- Delegate methods for UserNotifications :  -   //Called when a notification is delivered to a foreground app.
 -(void)userNotificationCenter:(UNUserNotificationCenter *)center willPresentNotification:(UNNotification *)notification withCompletionHandler:(void (^)(UNNotificationPresentationOptions options))completionHandler{
NSLog(@"User Info : %@",notification.request.content.userInfo);
completionHandler(UNAuthorizationOptionSound | UNAuthorizationOptionAlert | UNAuthorizationOptionBadge);
}
 //Called to let your app know which action was selected by the user for a given notification.
 -(void)userNotificationCenter:(UNUserNotificationCenter *)center didReceiveNotificationResponse:(UNNotificationResponse *)response withCompletionHandler:(void(^)())completionHandler{
 NSLog(@"User Info : %@",response.notification.request.content.userInfo);
  completionHandler();
  }
 
- Push Notifications Entitlements : From project target’s Capabilities tab and add Push Notifications Entitlements.
 
 
- Add push and mobile certificate properly. Hope this is everything you need! 
For more info: http://ashishkakkad.com/2016/09/push-notifications-in-ios-10-objective-c/