In a story, war and conflict can greatly shape ideas. They can introduce the idea of survival, making characters think about how to stay alive in a harsh environment. For example, in 'Lord of the Flies', the boys are in a state of conflict and the idea of basic survival becomes central.
One idea could be a power struggle between different magical races. For example, elves who have long been in control of a certain magical forest might face a challenge from a newly emerged race of dwarves who also want to harness the forest's magic. This could lead to battles, political intrigue, and a fight for the loyalty of other races in the fantasy world.
A conflict within a character can be very interesting too. A person who has always been taught to be honest but is suddenly faced with a situation where lying could save a loved one from a great harm. The internal struggle between their moral values and the love for their family member is a powerful source of conflict.
Magic misuse can cause conflict. For instance, if a powerful mage starts using dark magic to gain more power, it begins to corrupt the land around him. The local villages and the ruling lord's forces will be in conflict with the mage. The villagers are suffering from the effects of the dark magic, and the lord wants to maintain his territory. At the same time, there may be other mages who are split between trying to stop their former colleague and being intrigued by the power he's amassing.
One common idea is the futility of war. Stories often show how war destroys lives, families, and communities without really achieving much in the long run. For instance, in 'All Quiet on the Western Front', we see the senseless killing and destruction that war brings.
I'm not sure which specific story you're referring to. Amelia could potentially be a hero, a victim, or a catalyst in the war conflict depending on the plot.
One idea could be a character's internal conflict between following their dreams or fulfilling family expectations. For example, a young artist who wants to study art in Paris but their parents expect them to take over the family business. This creates a strong conflict as the character has to decide between their passion and their sense of family duty.
Person vs. society conflict. For instance, a character in a dystopian society who rebels against the strict laws and rules that suppress individuality. The character might start a small act of resistance like writing subversive graffiti, which then escalates as the authorities try to hunt them down.
In a fantasy story, a great conflict idea is the clash between the old magic and the new magic. The old magic users, who follow traditional and perhaps more ethical ways, see the new magic as a threat to the balance of the world. It could also be a conflict where a hero has to choose between saving his true love or saving the world from an ancient evil. And there's the conflict of a young wizard who discovers that his family's magic has been cursed and he has to find a way to break the curse against the will of an evil sorcerer who placed it.
One idea could be a conflict between a character's ambition and their moral code. For example, a young scientist is desperate to make a groundbreaking discovery but the only way to do so involves unethical experimentation on animals. This creates an internal struggle as the character has to decide between achieving their life - long ambition and staying true to their principles.