Help 7 months old Ozi, a dog with cataract

Ozi is 7 months old dog. He was adopted with his brother by me 5 months ago. They are crossbreed dogs. At the start Ozi was hitting a furniture. I thought he does it becouse he is just clumsy. Two months later it was still happening. I went to the vet with him and he said that Ozi has a cataract. I was totally shocked. The vet said also that Ozi will completely loose his sight during next 2 months.