Call Of Duty 2 issue

Call of Duty 2
I recently purchased a copy of Call of Duty 2 from ebay and neglected to notice that it was a stock photo and it turns out the actual product is in another language although I successfully loaded the english version with the included instructions.

There was no CD key and it turns out I cannot play online.
My questions are ,

are any of you familar with these types of CDs and is there a fix for online play?

Also I’d appreciate some reviews from those who have or are playing COD2 online.
How good is it? Much better than MOH? Much Better than COD1 online?

I’m trying to determine how much effort it’s worth.