Maybe you don't have SDK components properly installed. Run your Android SDK Manager and make sure you have these things installed:
- Android SDK Build-tools
- at least one API is installed
Below is the screenshot when running my Android SDK Manager. There you can see I'm using Android 4.4.2 (API 19), you need at least one API installed. You can use other than API 19 but you may need to make necessary changes on the settings.
This is how to start the Android SDK Manager:
My SDK folder is ~/Android/android-sdk-linux
You may need to change the line #2 below to browse to yours SDK folder
01. Start your Terminal
02. cd ~/Android/android-sdk-linux
03. cd tools
04. ./android
if line #4 does not work for you, you can try
05. cd bin (or maybe: cd bin64)
06. ./sdkmanager
The SDK components are large, instal only what you need (and remove those you don't need) to reduce the download time.
Note:
I haven't updated my SDK and NDK for quite a while, things may change but the concept should be the same.