Fu's plan: He got angry that his lab was destroyed, which by effect weakened the chains to the prison planet. The planet (5 planets and one sun) exploded while CC UI Goku, Cumber, Ozotto and the other prisoners minus Trunks and Cooler were on it. It is not known what happened to those who were on the planet but Xeno Goku said CC Goku will survive
Fu lost some of the energy he collected, so in an act of revenge he is going to create a big bang and thus a new universe on top of universe 7, which might possibly destroy it (Fu isn't sure what will happen to universe 7 but he doesn't care)
The next arc is about stopping Fu before he does this. After that it's the fight with Prime Mechikabura, who's trapped Chronoa and presumably is turning her into a demon god, while taking her powers and becoming the supreme kai of time. The teaser for Mechikabura arc has him standing in the middle of space with his presence creating black holes and eating away the universe