Reverse engineer an android app and duplicate the hosting server

I have an android app that enables a user to download a song, sing and record then share the recording. I did not build the app, so I don't have the source code. The application comes with one song. I would like to use my own songs that I have developed. My songs are 10 in total. TASK 1. Learn the current operation and mechanism that is used to download the one song that comes with the app.(Both in the app and on the online server) 2. Set up a similar system on my server, where we shall have my 10 songs. 3. Set up an admin backend to enable me to add more songs in future. The platform that will be developed on our server should function exactly the same way as the original platform. I have attached the apk. Kindly, first download the app and check if you can manage the task, if yes, proceed to bid. I need this done ASAP. Thanks