hello, im new here, i bought and play PoE, i like this game. I want ask you please. I killed the Thaos now and i dont know how to continue. How can i continue to White March ? sorry for my english.

You can't. Thaos is the end of the game. After jumping into the pit there's no coming back. You'd need to load a savegame from before jumping into the pit. White March is a DLC that is best played at mid levels (from lvl 8 on). It's not an expansion that you play after the main game is done but rather interwoven additional content that you can play parallel to the main plot line like a big side quest.

oh i didnt know that, thanks for your help...