Hey guy, eminem has some pretty serious dawgs working the mixer on his productions. We are talking guys that have been engineering for many years, and/or who have apprenticed under other big named engineers to learn their skills.
They also have spend HUGE amounts of time mixing music.
They also probably start out with better sounds than you did.
I would estimate that I have spent at least 10,000 hours in my life at a mixing board mixing music in either studios or doing live sound.
Do the math on what that translates into full days!
You need to put YOUR hours in my man. I could tell you what I might do for a certain mix, but that might not be what YOU WANT!
It is all subjective.
You should should start out with some specific questions about what you are hoping to change.
I listened to those first two songs. They don't sound that bad. They don't sound big time, but I have heard MUCH worse too! So, you have done "ok" for being a total newb to mixing.
You aren't going to learn it all overnight, and you probably at this point haven't yet figured out what you DON'T know yet.
You have to learn about what eq does, what the different parameters of an EQ does, then experiment with different eq's and see what they do well for any particular part you are applying it to.
Then you have to learn all of that for compression, limiting, reverb, echo, etc....
It is a life time of learning.
If you want it to all sound GREAT RIGHT NOW, hire a professional who has done work that you have heard that you like.
Otherwise, be prepared to spend the next couple of years doing mix after mix after mix.
Mixing is really not something you can teach a person, and few are going to go into too much detail about what they would do for your mix unless you pay them. Trying to do it over the internet is VERY hard to do because you can talk a hell of a lot faster than you can type!
Good luck.