Well in the description it clearly stattes that:
Congratulations! You've completed the 8th quest.
You get 12 cruisers and a code key.

now.. where is the code key? do i have to reach a lvl of smthn or do smthn for it? it never explains...

can i get some info on this? plz?

In this case, the Code is a conditional phrase. There are no any Physical code in this quest. The only real code that you can buy after passing the tenth quest to activate Toss.