how do i create this sound

could anyone please help me create a similar arp like here from the very beginning: https://youtu.be/BtFuVOOvN-8?si=vI1LqAH7mpe9lCQP

i like deconstructing my favorite songs and been really stuck with this arp sound, i really cant get any peace knowing i cant get close to the sound

i tried pitching it down to get the notes progression and tone of the sound, someone said it’s saw wave processed with lofi effects but i still cant replicate it. please help 🙏🏼