Previous owner before me had a old alpine installed. I bought a new pioneer unit so I could use a auxiliary cord for music.

I'm trying to remove the old alpine but it has cords in it that are like BUILT IN to the back of the stereo so I have no clue how to pull these cords out.

 

The first picture would be the low level inputs. You need to follow these wires to where the connectors are on the far end. It shouldn't be more than 8-10"
The other one is the antenna cable. You have the connection point in the second picture. Just pull the silver part with the crimp marks on it and it will come out.

 

You can re use the harness adapter, the white plug with the bundle of wires leading to it.
Just cut the wires at the connectors and attach to the matching colors on the pioneer harness.

Like said above, the other sets are going to rca cables somewhere, or are just tucked into something in the dash. If they are hooked to rca's( for an amp ), then you will need to extend them to reach the plugs on the new radio, or if there is enough slack, pull them up to the new radio.
If you aren't running an amplifier, there may still be rca's attached from a previous install. If you are not going to run one, you don't have to worry with hooking them back up.

The antenna plug should be a straight swap.

 

those old alpines have a separate amp unit apart from the head unit, should be a square box with a heat sink. they make adapters to plug RCA cables into the alpine amps then you can use it if you want, they normally use a DIN plug instead of RCA jacks on the alpine stuff