If we think logically you cannot! It is very very and very tough for you to complete the trek solely. Remember Chadar Trek is not a joke. It is in one of the most difficult trek in India. You never know the about the weather. if you are going solely you might get logistics issue. Trek leader and respected companies have proper arrangements of any emergency and have certified trek leader and in this trek you definitely need all those.:)
It is not recommended... The Chadar Trek is one of the most difficult treks in India...The trek is 105kms journey covered in 9 days. The weather conditions are harsh and altitude ranges around 11000ft.It requires a great level of experience to understand which parts of ice to walk on.....