Answers for "how to find where android sdk is installed"

install android sdk

Android SDK is bundled with Android Studio
(this is the easiest way to install and use the SDK)
https://developer.android.com/studio

Or you can install it seperately
https://developer.android.com/studio#command-tools

install android sdk via terminal

sudo apt-get install libc6-dev-i386 lib32z1 openjdk-8-jdk