What is most important in Gaming? GPU or CPU?

Neither of those two has a "Gaming GPU" in it.  Anything below "n50" from nVIDIA is only for viewing movies on DVDs, or for watching various streaming video channels.  Even the better of the two isn't close to good enough.  To avoid playing at CRAWL speed, the graphics will have to be as low as they can go, and the same for the screen resolution.

All of nVIDIA's mobile video cards are badly crippled and poorly supported with badly engineered drivers.  Avoid those products completely. 

However, if you must insult the ecology with a laptop, instead of the much greener choices of stationary computer systems, seek out machines with AMD Radeon GPUs from the R9 series.

When looking at any system's specs, the GPU is both the most important, and the most critical hardware component.  The CPU comes in second. 

Star Wars Battlefront

Minimum PC System Requirements

    OS: 64-bit Windows 7 or later (Win 7 should have SP 1)
    Processor (Intel): Intel i3 6300T or equivalent (3.3 GHz)
    Memory: 8GB RAM
    Hard Drive: At least 40 GB of free space
    Graphics card (NVIDIA): nVidia GeForce GTX 660 2GB
    Graphics card (ATI): ATI Radeon HD 7850 2GB
    DirectX: 11.0 Compatible video card or equivalent
    Online Connection Requirements: 512 KBPS or faster Internet connection

The minimum 660 is a DESKTOP GPU, the real thing, not HALF of anything, and more than twice as fast as the most generous laptop GT 640's speed. 

To create something CHEAP, an Optimus is only the BACK HALF of a real GPU. 

Thank so much for answering me. I understand that a stationary computer system is better in many ways,but I really need something that I can take with me, something portable. So do you suggest me taking the one with the better GPU?

The first one is better for gaming, but neither of those two is good enough to run this game. The CPUs are also dual cores (with hyperthreading) if I'm not mistaken, and almost every game nowadays requires a quad core.

I suggest you keep looking. You could ask for advice on https://www.reddit.com/r/suggestalaptop

You could also tell us your budget and country, and maybe I'll find something for you.

Thank you so much for helping me!!!

My budget is 700-1000 EUR for a gaming laptop.My country is Greece (If that helps?)🙂

That's a bit tough, because I don't know any Greek hardware stores. You'll likely find better advice by using the subreddit I linked to.

I will use the subreddit you  linked  me and I hope I'll find a good deal!

Thanks again for your help!