How is it possible to export the wpa_supplicant.conf from tablet? My tablet is connect to a wifi requiring EAP method, phase 2 authentification, login+password and proxy. and It works well.

The thing is i want to do the same for a RPi, but I don't know how to provide it with these wifi infos. Thus, I'd need to export the wpa_supplicant.conf it use it on my RPi.

Note : I can't root my tablet.

How would it be possible? Thank you (please be explicite, I don't master this field very well)
I don't know what are you trying to accomplish. 
I think you want to get wpa_supplicant.conf file, just go to system/etc/wifi and there is  your file just copy it, it should be possible without root, I don't have root and managed that.