It varies. In certain comic arcs, Lana Lang may face life-threatening situations but doesn't necessarily die. The fate of her character can change based on the creative direction of the writers and the demands of the story.
Lana Lang is a character in DC Comics often associated with Clark Kent (Superman) from Smallville. She's been depicted as a friend and sometimes love interest of Clark.
Lana Lang did not marry Lex in the comics. The comic plots didn't lead to such a union. Their characters had separate developments and romantic involvements.
One interesting story could be where Lana Lang somehow gets transported into the Harry Potter world. Maybe she uses her knowledge from her own world to help the Hogwarts students in a unique way, like using her skills in journalism to expose some dark secrets in the wizarding world that the Daily Prophet has been overlooking.
You can start by looking on popular fanfiction websites like FanFiction.net or Archive of Our Own (AO3). They have a large collection of fan - created stories, and you can simply search for 'Harry Potter Lana Lang' in their search bars. There might also be some niche fanfiction communities dedicated to this crossover that could be a good source.