Builder cheated Forgery Cheque and Appartment is incomplete

Sorry Sir am not good in English. Myself Subramanian from Chennai. In 2016 we made a Joint venture agreement with Builder for 1 house for us and 1 house money for us but, still now building not yet finished. In 2020 April my father passed away because of Builder due to depression we loss home and money. In August 2021 builder sold all houses without fully complete, there is no proper parking, no varnish in door, no paint its totally incomplete. Appartment is still unfurnished, after long fighting and my dad death we are also in that appartment on Oct 2021, however still building is not yet finished and not giving a money for reamaining 10 lak. When we asked money he said that he invested in other construction so he advise us to wait for more time. Almost we are waiting from 2016 and i have lost myfather also. We have each 5 lakh cheque with no date and also we have 5 promissory notes from him each 5 lakh. As we said we will put the cheque if their is a cheating but, he simply said cheque will bounced and if we filed complaint he said that he get a bail within 2 days. He is fraud already I lost my father please help me.