Well its pretty hard to go into the entire story exactly..but I can give you the basic highlights
Waaris shows that Rudra pratap is an underworld don. He is basically feared amongst everyone and worshipped in a way. He has a son named Shankar who left his studying at a young age to protect and support his dad in their business. Shankar married Gayatri who excpeted him even though she knew what kind of family he belonged to in an effort to change his ways. Gayati was pregnant with a baby but she lost that baby in a fight that broke out at a mandir. She left Shankar because of it. But they are now back together. Rudra has another son named Shourya who is unaware of the entire underworld leadership his father has and that his family is apart of mafia. Shourya has stayed at boarding school. He is in love with a girl named Simran. Simrans brother Kulbhushan disapproved of their relationship. Things happen and Simran ended up leaving Shourya after she finds out he is apart of a mafia family. Shourya, because of misunderstandings doesnt know why simran left only that she moved to london. He goes to his dad for help but his dad refuses. He doesnt want Shourya to marry Simran. Shourya is upset right now with his father because his refusal to help him find simran and because Rudra wants him to marry a girl named Ganga. So he hasnt been shown in recent episodes. Ganga is the sister of Rudras late friend accomplice, helper who he had high regards for. He promised his friend that he will take care of Ganga so he does, and also decides to have Shourya marry her. Ganga at first refused to marry him because Shourya wasnt happy about it. Rudra lied and pacified her into thinking that he did accept, so now Ganga has accepted shourya to be her husband. They arent married yet though. Rudras last child is Swati. Swati was unaware of the families mafia leadership as well until a while back. When she found out she in a way distant herself from her family. She fell in love with Dharma. Dharma was a childhood friend and has grown up to help Rudra in his business just like Shankar. He was close to everyone, and was almost a son of the family. Swati and Dharma fell in love and when Rudra found out, he had Shankar kill him.
Okie..so that was the basics..hope that was good enough.