Transfer of shares

My father who is very old in age and bought SBI shares before demat era. Either he purchased shares in his names or my mother’s name and my sister’s name also. These shares are in physical share certificates formats in these respective holders name.
My father can no more do any trading activity due to his old age and wants all these shares (bought in his names singly or jointly with my mother’s name or my mother’s name singly or in my sister’s name singly) to be transferred to my name singly.
My query is how all these shares can be converted in my name?

@Baidurya_Sarkar

The shares have to be dematerialized first in the respective share certificate holder’s Demat account.
If it is a joint share certificate, then a joint Demat account has to be opened and the physical certificates have to be dematerialized here.
Once the shares are available in the Demat form in their respective accounts, a DIS(Delivery Instruction Slip) of the concerned broker has to be filled with the share details meant for transfer.
You have to provide the Demat details(DP ID and DP Account Number) of your target Demat account to that concerned broker processing the DIS slip and the shares will then be transferred to your account.

This is Zerodha’s Dematerializion Request Form.

And this is how you typically fill a DIS slip.