Removal of name from housing documentation and change of nominee

Hello, My parents jointly purchased a flat in Dombivli and their name was jointly added on the share certificate and other housing documents. My father passed away earlier this year and we (wife and the children), would like to remove his name from the share certificate and any other documentation related to this flat and only leave my mother's name on it so that she is the sole owner/holder. Also, we would like to change the nominee for the flat from the son to one of the daughter so that she can inherit it after our mother. What is the process to be followed for the following: 1) Legally removing my father's name from the share certificate and registrar records (flat is in Dombivli) and only leaving my mother's name on it so that she is the sole owner. 2) Removing the son's name from the flat nomination and replacing it with one of the daughter's name. Also, if there are any other procedures to be followed to complete the above two steps, I would greatly appreciate if someone could advise of the same. Thank you in advance!