The main themes in 'Room' based off a true story include trauma and recovery. The characters have experienced a great deal of trauma while being held captive, and the movie shows their journey of recovering from that. Family is also a big theme. Despite the abnormal situation, the mother and son form a strong family unit within the room. And there is the theme of perception. The boy's perception of the room as his whole world at first and then how that changes when he experiences the outside world.
In 'Room' based off a true story, there are several important themes. Resilience is a major one. The characters, especially the mother, show great resilience in the face of such a difficult situation. There's also the theme of identity. The boy has to figure out his identity in the outside world after growing up in the room. And the theme of hope. Throughout the movie, there is a glimmer of hope that keeps the characters going, whether it's the hope of escape or the hope of a better life after they are free.
One key theme is captivity and freedom. The characters are held captive in the room and then have to adjust to freedom. Another theme is mother - son relationship. The mother's love and protection for her son are very prominent. Also, the theme of survival, as they find ways to survive in the difficult situation in the room.