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.
The Melody is a 100% royalty free loop from Splice.
The Drums I made from scratch.
Sample pack Splice Originals - Glow Fi
Loop name SO_GF_130_melodic_stack_resin_Amaj