Okay so before I get to the mix, this song is REALLY GOOD so far... I'd say that the part from :18-:24 should probably change cause it throws the vibe off in my opinion but the second part of the drop is excellent it reminds me a lot of WRLD But with the mastering it's really really quiet but that's an easy fix (if you want help with that just let me know) and the mix has some weird clipping static jaunt going on in there that doesn't necessarily ruin the song but it definitely takes away from it. But with that being said once those issues are fixed it'll be a fantastic song you just need to make sure that your leads are EQ'd so the bass comes through clearly and make sure that your high end is EQ'd properly so that static/clipping mess isnt there.

A lead and a bass do occupy to different parts of a songs spectrum but the important thing to note is where it occupies the most... Sub bass (808 bass/sine wave bass) occupies from about 30 to 200 hz while supersaws and things like that occupy pretty much from 200 hz and up (as far as your mix is concerned) But with that being said, if you put 2 sub basses on top of each other, then it sounds like shit and its the same thing if you have too much going on all throughout your songs mix. If you have too much in the highest end (17500 hz+) then the song will have this clippy/white noise-y sound to it and if your song has a lot going on from 30-200 hz then your mix gets really messy sounding (rumbling from overlapping bass and quieter bass from being buried under everything else) and I know its a lot to understand right now and you'll get better at it as you do it more (TRUST ME I'VE BEEN WHERE YOU ARE) just give it time and practice the right way to do these things now so you don't have to worry so much about the mix and you can worry more about the music Hope this helps!