Teenager Writing a song, need music, acoustic basically.?

Im trying to write a song, taylor swift inspired me, im 17 and i want
to write about a past relationship, but its so hard without a rythm
and music and i dont know how to play any instruments so where can i
get or make music for my song completely free? Im looking for
acoustic, no hip hop or techno, acoustic! Im a teenager. Please and
thank you!