I dunno how to make music and I'll be making the game all by myself.
is this allowed?
There are lot of people who offer here music for free like me. Just search through music assets and find what you need. https://itch.io/game-assets/free/tag-music there are lot of people who offers loops so you just need to put it in project without edited. Music from games is under copyright you might have problems of putting video of your game to youtube or disqualify from jam.