Well, it depends on which specific DC Comics storyline you're referring to. In some arcs, Firestorm has met his demise, but the character's fate can vary depending on the creative direction of the writers.
Well, Firestorm's origin is pretty cool. It all started at a nuclear power plant. Ronnie Raymond was there for some reason, and Martin Stein was working on some important scientific stuff. Then boom! There was an accident. Their bodies and minds got fused together in this wild way. And just like that, Firestorm was born. He has the ability to manipulate nuclear energy and has a really distinct look with his fiery appearance.
Well, in the comics, Firestorm is usually a combination of two characters with the ability to control and manipulate energy. They can transmute matter and generate powerful blasts of heat and energy.
The key elements are the nuclear accident, Ronnie Raymond, and Martin Stein. The accident was the catalyst that brought their atoms together to form Firestorm.
There could be a fanfiction where the Firestorm element is combined with Naruto's friendship with Sasuke. Maybe in a battle, Naruto uses the Firestorm to save Sasuke from a great danger. This would not only show his power but also the depth of their bond. It could also explore how Sasuke reacts to being saved in such a spectacular way.
One popular Firestorm OC fanfiction could be 'The New Flame of Firestorm'. It might introduce a unique original character who has special powers that interact in an interesting way with Firestorm's abilities. Another could be 'Firestorm: The OC Alliance' where the OC teams up with Firestorm to fight against a common enemy.
Another important aspect is character development. Your OC should not be a static character. They should learn, make mistakes, and change throughout the story. For instance, if the OC starts out as a bit of a loner, they could gradually learn the value of teamwork through their adventures with Firestorm. Also, make sure to proofread your work to avoid grammar and spelling mistakes that can detract from the overall reading experience.
To start writing Naruto Firestorm fanfiction, you should do a lot of research on the Naruto world. Know the existing powers, the characters' personalities, and the overall lore. For the Firestorm part, you can be creative. Maybe it's a power that was lost long ago and Naruto stumbles upon it. Outline your story first, with a beginning, middle, and end. For example, the beginning could be Naruto's first encounter with Firestorm, the middle his training and challenges, and the end a big battle where he uses it to save the village.