i explore all the map and talk with everyone and i don't know how access to the new dungeon, someone can help me please

i assume you met Frode during the day and did his seed gathering quest, so you need to meet Horace in front of the tavern, still during the day, ask Jorgen about his horse and show up around the village 3 days later (still when there's still light outside) to start the election quest, just finish it (save before bringing the votes to Einar maybe)