At GGn I saw to promote to Gamer level we need 600 points. we can get them when we upload 1TB and for Pro gamer we need 1200 points (6TB). Is that just like? Or I missed something?

It's not simple as that.

Userclasses gain by getting points from achievements , here : https://gazellegames.net/user.php?action=achievements

Hover your mouse on each icon, it will tell how much you are required to earn for achievement to get the points.

Got it. I supposed that only uploading gives you points. But there are other ways too.