1. You have to obtain probate for the WILL. In some States of India, it's not a must and in some States it's a must. For example in Karnataka, probate of WILL is not mandatory.
2. You can get the property transferred/mutated in your name in the jurisdictional Revenue Office/Corporation/Municipality on the basis of your father's WILL in your favour and his death certificate.
3. Khatha/Patta, as the case may be, indicates your name as the present owner instead of earlier owner (your father).
4. Based on Khatha/Patta in your name, you can sell the property to any prospective buyer. There's no need to register the property in your name before selling it.