In this fanfiction, Harry could be magically transported to a parallel universe where he has no friends or allies at first. He has to rely solely on himself. He quickly learns to adapt. He starts by making his own wand using the resources available in this new world. He then figures out how to create a shelter using magic. He hunts for food, discovers new spells by trial and error, and slowly builds his own power base. As he takes care of himself, he also discovers hidden strengths within him that he didn't know he had before.
One possible plot could be that after the death of Dumbledore and with the Order of the Phoenix in disarray, Harry decides to go into hiding alone. He uses his skills in magic, like the Patronus charm for protection and the Invisibility Cloak to avoid detection. He might start to forage for his own food in the Forbidden Forest, using magic to find edible plants and hunt small magical creatures in a humane way. He also spends his time studying advanced magic on his own to become stronger, preparing for the final battle against Voldemort.
Perhaps Harry gets fed up with all the adults trying to control his life and protect him in their own ways which often end up putting him in more danger. So, he runs away. He finds an abandoned cottage in the countryside and uses magic to make it habitable. He grows his own magical plants for potions and food. He practices defensive spells on his own, using the natural elements around him as targets. He might also befriend some local magical creatures who help him in his self - sufficiency journey.
Well, maybe Harry discovers an injured snake in the Forbidden Forest. He decides to take it back to the Gryffindor common room and hides it in his trunk. He uses his magic to heal the snake and then starts to feed it small magical creatures. Eventually, the snake becomes his secret pet and helps him out in some tricky situations, like warning him of approaching danger.
Maybe Harry discovers a baby snake in the Forbidden Forest and decides to take it under his wing. He could use his Parseltongue ability to communicate with it and keep it hidden from the other students and teachers.
Obviously, Harry Potter himself is the main character. Then there could be some magical creatures like the Kneazles. They are intelligent and could sense Harry's situation and help him out, maybe by guiding him to food sources or warning him of approaching danger. Hagrid might also make an appearance in the form of memories or hallucinations that guide Harry in his self - care journey, as Hagrid was one of the first people to introduce Harry to the magical world and taught him some basic things about taking care of magical creatures.
One possible plot could be that Harry, using his magic skills, protects Naruto from the various threats in the Naruto universe. For example, he could use spells to shield Naruto from enemy ninjas' attacks. He might also use his knowledge of magic to help Naruto understand some concepts that are difficult in the ninja world, like a different way of looking at chakra manipulation which could be related to how magic works in Harry's world.
Well, Harry might use his magic to make the baby laugh. For example, he could turn the baby's rattle into a little magical creature that dances around. He'd probably also be very protective, like how he was with his friends at Hogwarts.
One possible plot could be that Harry discovers a time - traveling accident has brought baby Snape to his present. Harry, being the kind - hearted person he is, takes it upon himself to care for the baby. He has to figure out how to feed the baby, keep him clean and comfortable. Maybe he also has to protect baby Snape from any threats in the wizarding world that might target Snape even as a baby.
One possibility could be that Draco is forced into taking care of Harry due to some magical circumstances. Maybe there's a spell gone wrong that makes it his responsibility. He initially resents it but as he spends time with baby Harry, he starts to see the innocence in him and develops a soft spot.
Well, Naruto might be really confused at first. He's from a world of ninjas and suddenly has to take care of a baby wizard. He'd probably use his ninja skills to protect Harry. For example, he could set up traps around the house to keep bad guys away. And he'd surely try to feed Harry some ramen, which might be a bit strange for a baby used to wizard food.
Well, perhaps the plot could involve Harry having to fend for himself from a very young age in the wizarding world. He might have to figure out magic on his own, without much guidance from adults. Maybe he starts exploring the secrets of Hogwarts by himself earlier than in the original story, leading to all sorts of unexpected adventures.
One possible plot could be that Harry, after years of feeling unappreciated or burdened by his fame in the wizarding world, decides to disown himself. He might leave Hogwarts and the wizarding community behind, perhaps to live as a Muggle. He could change his identity and start a new life, away from the constant danger and expectations that come with being Harry Potter.