Hi, karika...
0) Configure paths... lazarus menu: "Tools" ---> "[LAMW] ...." --> "Paths Settings ..."
1) Your project construction is incorrect... please, do:
menu "Project" ---> "New Project" ---> "LAMW [GUI] Android Module"
2) after project construction put your "mp3" file in project folder "assets" ...
[ex. pipershut2.mp3]
3) Put a jButton and a jMediaPlayer on the form...
4) handle the button "OnClick" event:
procedure TAndroidModule1.jButton1Click(Sender: TObject);
begin
jMediaPlayer1.LoadFromAssets('pipershut2.mp3');
end;
5) handle the jMediaPlayer "OnPrepared" event:
procedure TAndroidModule1.jMediaPlayer1Prepared(Sender: TObject;
videoWidth: integer; videoHeight: integer);
begin
jMediaPlayer1.Start();
end;
6) Connect your device by usb cable... [you need active "mode developer"]
7) lazarus menu "Run" --> "[LAMW] Build Apk and Run"
..............Listen to the sound and enjoy!
note: there are some help here:
https://github.com/jmpessoa/lazandroidmodulewizard/blob/master/LAMW%20Getting%20Started.txt