Porting to Android Project Then Integrating AdMob SDK

Hello! I have been trying to add SDK of admob in my android project which is built from Unity3d.

This is my AndroidManifest.xml.

 <?xml version="1.0" encoding="utf-8"?>
     <manifest xmlns:android="http://schemas.android.com/apk/res/android" android:theme="@android:style/Theme.NoTitleBar" android:versionCode="1" android:versionName="1.0" package="com.company.ProductName" android:installLocation="preferExternal">
       <supports-screens android:anyDensity="true" android:largeScreens="true" android:normalScreens="true" android:smallScreens="true" android:xlargeScreens="true" />
       <application android:icon="@drawable/app_icon" android:label="@string/app_name">
         <activity android:label="@string/app_name" android:screenOrientation="portrait" android:launchMode="singleTask" android:configChanges="mcc|mnc|locale|touchscreen|keyboard|keyboardHidden|navigation|orientation|screenLayout|uiMode|screenSize|smallestScreenSize|fontScale" android:name="com.company.ProductName.UnityPlayerNativeActivity">
           <intent-filter>
             <action android:name="android.intent.action.MAIN" />
             <category android:name="android.intent.category.LAUNCHER" />
           </intent-filter>
           <meta-data android:name="unityplayer.UnityActivity" android:value="true" />
           <meta-data android:name="unityplayer.ForwardNativeEventsToDalvik" android:value="false" />
         </activity>
         <activity android:configChanges="fontScale|keyboard|keyboardHidden|locale|mnc|mcc|navigation|orientation|screenLayout|screenSize|smallestScreenSize|uiMode|touchscreen" android:name="com.facebook.unity.FBUnityLoginActivity" android:theme="@android:style/Theme.Translucent.NoTitleBar.Fullscreen">
         </activity>
         <activity android:configChanges="keyboardHidden|orientation" android:name="com.facebook.LoginActivity" android:screenOrientation="portrait" android:theme="@android:style/Theme.Translucent.NoTitleBar.Fullscreen">
         </activity>
         <activity android:exported="true" android:name="com.facebook.unity.FBUnityDeepLinkingActivity">
         </activity>
         <meta-data android:name="com.facebook.sdk.ApplicationId" android:value="\ 1470874689796550" />
       <activity android:name="com.google.ads.AdActivity"
               android:configChanges="keyboard|keyboardHidden|orientation|screenLayout|uiMode|screenSize|smallestScreenSize"/>
        
       <activity android:name="com.amazon.device.ads.MraidBrowser" android:configChanges="keyboardHidden|orientation"/>
     
     <activity android:name="com.amazon.device.ads.VideoActionHandler" android:configChanges="keyboardHidden|orientation|screenSize"/>
       </application>
       <uses-sdk android:minSdkVersion="9" android:targetSdkVersion="19" />
       <uses-feature android:glEsVersion="0x00020000" />
       <supports-gl-texture android:name="GL_OES_compressed_ETC1_RGB8_texture" />
       
        <uses-permission android:name="android.permission.INTERNET" />
     <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />
     <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />
     <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
     <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
     </manifest>

This is my OnCreate() in java.

 protected void onCreate (Bundle savedInstanceState)
     {
         requestWindowFeature(Window.FEATURE_NO_TITLE);
         super.onCreate(savedInstanceState);
         
         getWindow().takeSurface(null);
         setTheme(android.R.style.Theme_NoTitleBar_Fullscreen);
         getWindow().setFormat(PixelFormat.RGB_565);
 
         mUnityPlayer = new UnityPlayer(this);
         if (mUnityPlayer.getSettings ().getBoolean ("hide_status_bar", true))
             getWindow ().setFlags (WindowManager.LayoutParams.FLAG_FULLSCREEN,
                                    WindowManager.LayoutParams.FLAG_FULLSCREEN);
 
         int glesMode = mUnityPlayer.getSettings().getInt("gles_mode", 1);
         boolean trueColor8888 = false;
         mUnityPlayer.init(glesMode, trueColor8888);
 
         View playerView = mUnityPlayer.getView();
         //setContentView(playerView);
         playerView.requestFocus();
         
         setContentView(R.layout.modal_overlay_container);
         
         // Look up the AdView as a resource and load a request.
         AdView adView = (AdView)this.findViewById(R.id.adview);
         adView.loadAd(new AdRequest());
         AdRegistration.setAppKey("0123456789ABCDEF0123456789ABCDEF");
       
         
     }

But ads does not show in the application. And when i run in emulator the application does not run at all. What is wrong? Can anyone help me?

P.S: Im beginner in android development.