Android Home Environment Variable Failed to Find

I almost completed coding of my app but when i type this command ionic build android than this error is appear
Error: Failed to find ‘ANDROID_HOME’ environment variable. Try setting setting it manually.
Failed to find ‘android’ command in your ‘PATH’. Try update your ‘PATH’ to include path to valid SDK directory.

How to solve this error please help me.

My path of Android Sdk is : F:\NIRAV\Android\sdk
My Project path : D:\hubtricks\hubtricks

please suggest me some command to solve this