i need help to compose music for my song

hi, im 18 years old guys from indonesia, i made one song "HangMan" but i dont know how to create d music melody and instrument, in here's learning music so expensive but i really want have a song, i really hope u help me compose my music, my song gendre is pop. n general song of sam smith n bruno mars. if u can help me i will send the lyric after this, thank you/terima kasih warm regards rafi. cheers