The base is original from the producer (chords and melodies), but is complemented with elements that complement the song that come from samplepacks, usually, vocal chops, guitars, wobbles sections, glitch effects. It is the standard in which most of producers work, in a project you will find MIDI files made by the producer, but also melodic loops.
Free use melody obtained from looperman. the entire process of creating the bass lines and hihats was produced by me. no midi files were used.
Sample pack Looperman
Loop name Travis Scott Future Cubeatz Type Sample Part 2