Lawand Hamadamin and his family left northern Iraq after reports the so-called Islamic State was ordering disabled children to be killed by lethal injection.
The family spent a year living in a tent in a camp in Dunkirk before leaving for the UK.
Lawand is now learning sign language at the Royal School for the Deaf in Derby.
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As the family made its way to Europe, Lawand's parents put a plastic bag on his head to protect his cochlear implant.
When they did eventually reach Dunkirk, the family was unable to charge the batteries for Lawand's implant and the boy lived "most of his life in a silent world".
After hiding in the back of a lorry to get to the UK, the family was first sent by the Home Office to Halifax but later relocated to Derby so Lawand could get specialist help.
Lawand's father, Rebwar Golbahar, said: "It is such a relief to be safe now and to be able to give Lawand some help to communicate.
"We are eternally thankful and grateful to the people of Derby and above all the school.
"We will never have enough thanks for the school."
Lawand had been unable to access sign language classes as it is not taught in Iraqi schools.
The conflict has also destroyed clinics and sent many doctors fleeing, meaning he had no access to treatment.
Helen Shepherd, head teacher at the Royal School for the Deaf Derby, said: "Most children are a little nervous on their first day of school but Lawand has faced so many greater challenges in his short life, he took it very much in his own stride."
The family of a deaf six-year-old boy who fled Iraq to avoid being killed said his school has saved his life.