Thank you @Sebastia !
I did a search in their help, but no result returned, but I guess It was a technical problem at the time.. they use a lot of external library to run their website…
So I’ve checked the two link you found ( again thanks )
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So for the configuration of the PPPoE they seem to not give a lot of details… 
But indeed on the post regarding the fritzboz they say ~“You can request the credentials by contact us”
So i’ll try to reach them… (finger cross)