Can you please check if my sentences are possible? Thank you

1)When she was born,the doctors noticed that she had a problem with her feet.
2)She was operated on her feet (?)/(She underwent an operation) and the doctors amputated her feet and part of her legs.
3) She didn't want to sit in (?) a wheelchair for the rest of her life. So she learned to walk when she was two.
4) When she was in her teens, she went to the Atlanta Paralympic Games and won three matches. She also starred in a fashion show for a famous clothes designer.
5) They diagnosed him cancer and told him that hsi chance of recovering was less than 50%.
6)His dad is in a wheelchair. His room is always in a big mess (I need a synonym). He had a talent for acting (or he had a natural gift for acting).
7) He enrolled at Dalesway Secondary when he was eleven.
8) He entered university when he was eighteen.

2. Her feet were operated on.

5. They diagnosed him with cancer and told him that his (sp) chance ....etc.

6. His room is always a disaster, untidy,
disheveled, messy, mussy, slipshod, sloppy, slovenly, unkempt.

Sra