Harry Potter could survive in the Forbidden Forest by making allies. He could befriend the centaurs or the friendly spirits in the forest. They could help him find food, water, and warn him of any approaching danger.
Well, he might have a lot of encounters with magical creatures. Maybe he'd befriend some centaurs or learn the secrets of the forest from them. He could also face more hidden and dangerous dark magic that lurks in the forest.
Maybe Harry discovers a hidden magical community in the forest. He could learn new spells from the forest creatures and use them to protect Hogwarts later.
He might encounter magical creatures that are not known to most wizards. For example, he could meet a rare breed of unicorn or a group of centaurs who take him under their wing and teach him their ways of magic and life in the forest.
She would use her extensive knowledge of magic. For food, she could use magic to conjure or transfigure things. She might also forage for non - magical plants that are safe to eat and use her knowledge of Herbology to identify them.
Hermione could be one. She might come to the forest to check on Harry and end up staying to study the unique flora and fauna which have magical properties. Another could be Hagrid. He loves all kinds of creatures and the forest is full of them, so he could visit Harry often and bring him supplies.
Yes, there might be. The idea of Harry Potter living in Big Ben is an interesting and creative concept for a fanfic. Writers often like to take familiar characters and place them in unusual settings to create unique stories.
Harry Potter himself is often a central character in these fanfics. Since he has a history of facing great challenges, it's easy to imagine him being drawn into the world of forbidden magic, either by accident or because he feels it's necessary to defeat a new dark force.
He might use his wand to cast spells for guidance. For instance, he could try the Point Me spell which would show him the direction he needs to go. This simple spell could be very useful in his situation.
Surviving in the Harry Potter fanfic universe would require a good understanding of the magical laws. Don't break the Statute of Secrecy. And be careful when dealing with dark magic. Avoid places known for dark magic activity. Another important thing is to have a reliable wand. A good wand can enhance your magic and protect you in dangerous situations.
There could be forest animals like wise old owls or friendly squirrels that interact with him.