How to recover loan from mortgagor who got loan through SIMPLE MORTGAGE DEED (without possession)

Hi Sir/Ma'am, In the month of February 2023, I lent a loan amount of Rs.1,00,000 to one Sayab through a SIMPLE MORTGAGE DEED (without possession) on the condition that the loan amount must be repaid within one year, i.e., by the end of February, 2024. But unfortunately, he has failed to repay the loan amount owed to me till date. Whenever I ask him to pay off the debt, he is reluctant and answers recklessly and nonchalantly. Having deeply fed up with his breach of trust, I approached the local PS in March of 2024 to resolve the matter. The SI at the station called up Mr. Sayab and asked him in a gentle manner to repay the loan. But a week later, Mr. Sayab sent me a legal notice (with a copy to DGP) accusing me of threatening him to vacate the property with the help of police and he also warned me that he would file a case against both me and the police. Now the issues before me are: 1. Is it mandatory to give reply to the Notice? 2. What's the time limit for Reply to the Notice (No time was mentioned in the Notice) ? 3. Should I go with Reply-cum-Legal Notice or only Reply? 4. Under which section should I file the suit for recovery of money? 5. How can I acquire his mortgaged property if he fails to pay what he owes to me? 6. Or please specify any other remedy to recover my money from the defaulter?