how to set root view controller in storyboard animated with navigation controller programatically

i have my login screen how ever i can able to skip that screen and go to home page when i am in the home page i could`d able to get my navigation controller in my home page i have embedded navigation controller with my login page have connectivity via push segue to home page every thing is good but nav bar is not coming in homepage if i try to embedded nav controller in homepage then also its not coming ... my code is

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    // Override point for customization after application launch.
     NSUserDefaults *defaults =[NSUserDefaults standardUserDefaults];
     
     if (![defaults boolForKey:@"registered"])
     
     
     
     {   NSLog(@"no user register ");
     UIStoryboard *storyBoard = [UIStoryboard storyboardWithName:@"Main" bundle:[NSBundle mainBundle]];
     ViewController *secondViewController = [storyBoard instantiateViewControllerWithIdentifier:@"LoginPage"];
     self.window.rootViewController = secondViewController;
     // then set your root view controller
     
     
     }
     
     else
     
     {   NSLog(@"user is daam sure registered");
     
     
     UIStoryboard *storyBoard = [UIStoryboard storyboardWithName:@"Main" bundle:[NSBundle mainBundle]] ;
         ;
     ABDB_CAMERAHOME *mainviewcontroller = [storyBoard instantiateViewControllerWithIdentifier:@"CameraHome"];
     
              self.window.rootViewController = mainviewcontroller;
        
         
         
     }
          
    return YES;
}

is their i am missing constraint about nav controller in program please suggest