There’s a reason why your Main Character is the Main Character. This might be because they have a particular skill or an emotionally compelling reason to be involved in the main conflict.
As an exercise freewrite for ten minutes on why your Main Character is the main character of this story. Consider what about the conflict is important to them, and why. Also consider how they feel about the conflict. What skills do they have to help them?
As a bonus, do this with your supporting characters about why they aren’t the Main Characters.