Anime Crossover: I Only Wanted to Lie Flat, but Became the Strongest?

After coming into this world, life seems to have no clear outcome or end. When I think about it, maybe it isn't such a big deal. Being someone who just gives up and coasts through life doesn't seem so bad, either. But I'm still a lone single guy, and I feel like I haven't really grown into a man yet. I'm honestly getting a little anxious. What should I do? Answers wanted ASAP, I'm in a hurry!

This novel and its characters are entirely fictional. Any resemblance is purely coincidental. Do not imitate.