Seeking URGENT assistance for below mentioned queries

Greetings, I’m 34 now and I married 3 years ago (Nov 2017) in UP, India (my native place) under Hindu marriage rituals as we both are Hindu. to a girl (31 now) I met through Shaadi.com (Aug 2017). Although, I have been living in Australia since early 2015 on temporary visa. Now I know that she married me to get Permanent Residence (PR) in Australia and was after my parental property knowing that my mother has cancer for last 12 years and my father was sick on and off. She was continuing her past relationships even after marriage in the background via her social networking sites while in Australia with me in 2018 that I found out last year. In Apr 2019, I booked her one-way flight to Mumbai, her native place. In May this year, my father passed away suddenly, she contacts me to ask what happened and if I was coming to India. I couldn’t go due to Covid lockdown and travel restrictions. Until June, I waited if she or her parents or any of her relatives will call or message me or my mother to console or to support mentally if not physically (I haven’t spoken to her parents or any of her relatives since April 2019). But that never happened and it became apparent that she/they only want my money because she can’t get the PR anymore as her visa is cancelled and I wouldn’t reapply. She didn’t take any action for 14 months. So, I filed a sole application for divorce in Australia in June. The court granted decree of divorce, which will be issued later this month on the basis of one party is domiciled in Australia and we do not have any child. Now she has sent me a lawyer's notice asking for her Streedhan, compensation of Rs 1 crore against the torture and dowry demands and maintenance of Rs 50,000 monthly. We never tortured her or demanded any dowry and all other points she has made are not true either. She and her parents always played and twisted with the words that I or my parents said, in their favour. In streedhan, she has claimed some jewellery, which is either made up or is with her already, we only have couple of items that I do not want to return behind the scenes to avoid further lies. She has got some belongings here with me in Australia and some in UP, India. I or my mother never denied giving any of it, it is just that I am not able to travel to India and my mother can’t travel either due to her illness and getting chemo every 3 weeks. I don’t want to parcel it either because then they can lie that they didn’t receive it or missing few items. We have asked her if she can travel herself/any elder and collect her belongings. She is alcoholic and stays out in hotels with guys, continues meeting guys over dating apps and lies about her whereabouts since the beginning. Also, threatened me with his boyfriend to ruin my career and future. I would like to know what actions can I take and how can I go about this notice? What is to be done to get this Australian decree to be valid in India? And what is the law in India in such cases? Thanks