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.
Process note
I produced this beat by combining multiple free royalty use melodic loops which are listed below. I used Waves, Soundoys, Fabfilter and Ozone 9 for FXs and engineering.
Melodic loops
Instrument Choir synth
Sample pack Soul Drip by Splice Original
Loop name SO_SO_117_melodic_stack_withoutyou_trappy_Emin