ios - how to create back button in navigation bar

Question

I have 2 page. first is tableView and second is view when I to click on any cell go on to next page (view) in way modal segue. I want add back button in next page of navigation bar . this is my code in view page : ViewController.m

- (void)viewDidLoad
{
    [super viewDidLoad];
    self.lable.text = obji.Name;
    self.lable2.text = obji.Descript;

    UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:@"Back" style:UIBarButtonItemStyleBordered target:self action:@selector(Back)];
    self.navigationItem.leftBarButtonItem = backButton;
}

- (IBAction)Back
{
    //I dont know that how return pervious page
}

Answer 1

As you said in your comment you use a modal controller

Add the following in viewWillappear

     UIBarButtonItem *backButton = [[UIBarButtonItem alloc] initWithTitle:@"Back" style: UIBarButtonItemStyleBordered target:self action:@selector(Back)];
     self.navigationItem.leftBarButtonItem = backButton;

And in

- (IBAction)Back
  {
    [self dismissViewControllerAnimated:YES completion:nil]; // ios 6
  }