Can I write a will. Property is in my father's name

My parents have expired . They didn't Left any will. There is a plot and house in my father's name. Me and my brother are legal heirs. I'm unmarried and want to donate my part of property to some charitable institution after my death . Since the property is still in my father's name ,can I still write a Will that my portion of property goes to charitable institution after my deat or the entire property will go to my brother after my death . Currently due to some personal reasons we are not able to distribute the property and have clear titles. Please suggest