I thought it was Helvetica but I don't think...
J'ai cru que c'était la police Helvetica mais j'pense pas...

Europa Grotesk No. 2  Suggérée par jerseygirl 

Finally I find it before, it's Europa. Thank !

Is there any website where I can buy this font FREE ?

Non, c'est une police commerciale. Si tu veux l’utiliser, il te faudra l'acheter.