Serious Landlord issues. How to proceed legally ?

Hello sir/mam I live in Chennai in a rented apartment of my ex company boss. Apartment consists of six house including my house. Only ground floor which I live is rent house rest all own their houses. A man who lives in 3rd floor keeps fighting with us daily and insults that we r jus tentant not owners. How can u use parking area for drying clothes. Why u nailed in wall etc. He speaking bad words to my old parents. They are very upset. And we do have a labrador dog which we keep inside our house. We don't tie r roam it outside of ur house. But he lies tat dog tried to bite and he don't like dogs in apartment to my owner. My owner permits me to keep dog but still he makes a problem. . He throws our clothes which we clipped in parking sides. In no way my parents harmed r used harsh words on him. But he abuses my parents very badly. Kindly give solution.