) My father has bought flat on the name of my mother how that flat is going to distribute after my mother, My mother has done my step brother bedakhal by publishing a news in newspaper. Registry is on the name of mother and father is co-borrower in home loan of the flat.
What is bedakhal?, if my understanding is right then he should have been renounced by your mother, right? This renouncement shall not deprive him of his legal rights in the property left behind by her as intestate, he can very well claim a legitimate share out of his mother's property as a lawful right.
2) My younger brother lives with parents, how movable property is going to distribute after parents.
The property being your mother's absolute property though your father has bought it but have done the registration on her name. Therefore after her demise, if she has not bequeathed the property in anyone's favor through a will, then shall devolve equally on all her legal heirs. The legal heirs will include you both, your step brother and your father
3) If me and my real brother got the share in flat. Then i do not want to live with him. Does i have right to sell it off and divide the money equally.
If the property has been bequeathed on yo both, then you both have equal rights in it. You may sell your undivided share in it or can seek partition and separate possession and sell yor share independently.