stop my father legally

Hello sir, i need some legal advice, I am the only son of my father, im married n have 2 daughter’s, I live with my father my step mother and my wife and daughters, i have always been the best son and running this house since many years after my father’s retirement But since few years my father’s and my step mother’s behaviour is very bad for me and my wife, now situation is really bad and I think my father has some physiological issue also he is threatening to kick me out of the house and planning to sell this house, house is on my father’s name but my father is paralysed, heart issue and many more diseases, I have a nice job and I earn well but I do not want to leave my father or this house in his such bad condition, my step mother and her family might take over all the money if our house sells, or my father will lose all the money due to his medical and mental condition
I Need some legal advice on this scenario what can I do that my father does not sell or can i claim anything or stop my father legally somehow
Please help