Filling form or any input element is not clear how to use it

[saiedtrife]

I am trying to fill form in website using browser on android device, and they problem is there is no clear way to locate the element

• PHP Version: 7.2
• Appium Version: latest
• Codeception Version: 2.4.2

Description:

1-I am trying to open chrome on android device and register form
So far I was able to : 1-Open chrome 2-click on button

$data = array('url'=>"myUrl");
       $I->setUrl($data);
       $I->getUrl();
       $I->implicitWait([ 'ms' => 3500, ]);
       $I->byCssSelector('#container-calculator > form > 
       div.calculator__button.calculator__button--promocode.form-group > a')
         ->click();

But when it came to sendkeys (filling input element),
There is no clear way how to do that, can please provide me with clear example!

Steps To Reproduce:

When I check the your code:

  /**
     * @param Element $element that accepts a string
     * @param string $keys send to $element
     * @return \PHPUnit_Extensions_Selenium2TestCase_Response
     */
    public function sendKeys($element, $keys)
    {
        return $element->setValueImmediate($keys);
    }

The problem is here you can't get the elementby ID like this:

`$I->getElement('#f_Last_Name');`
or other ways I tried 

Please add clear example how to open browser and fill form in android and Ios