Question: At the end when they destroy Starkiller Base, did it become the new sun for that star system? Because it sure does have the features of one after the implosion.
Question: How did Lor San Tekka get that map?
Answer: According to the 2017 book Star Wars: The Visual Encyclopedia, Luke Skywalker gave Lor San Tekka the map fragment to his location before he went into hiding on Ahch-To.
Why? Didn't he want to stay hidden?
Question: Why does Kylo Ren want to finish what Vader started? Why couldn't he just leave things the way they were? Why would he turn to the dark side just to finish what Vader started?
Answer: We don't know the reasoning behind Kylo Ren's motives just yet, but that will likely be gradually answered as the story unfolds in the upcoming sequels. Knowing too much about Kylo's backstory and his underlying motive early on would ruin the plot and eliminate any suspense leading up to the reveal.
Answer: Yes the sun was restored when the base was destroyed. Basically creating a new solar system.
lionhead