It could mean that someone is emphasizing that they are truly a girl in all aspects. Maybe it's a statement to assert one's femininity, perhaps in the context of facing some sort of disbelief or misunderstanding about their gender identity.
Once there was a girl named Lily. She loved to dress up in frilly dresses and play with dolls. But in her new school, some kids made fun of her girly ways. So she stood up and said 'I am all girl true story'. She then continued to be herself, showing everyone that being a girl was wonderful and she wasn't going to change for anyone.
One possible theme could be empowerment. A girl might be facing various challenges like discrimination or lack of opportunities, but she overcomes them and becomes empowered. Another theme could be self - discovery. She might be on a journey to find out who she really is and what she wants in life. And also, the theme of resilience is very likely. She could have faced setbacks, maybe in relationships, education or career, but she bounces back stronger.
No, 'I Am All Girls' is not based on a true story. It's a made-up narrative designed to engage and captivate the audience through fictional elements and plotlines.