I would like to do Pitru Paksha rituals, such as offering black til seeds and water to my ancestors, like my grandfather and great grandfather and maternal grandmother. My paternal grandmother and my parents are still alive. Traditionally, it would be my parents who are the ones to do it, but my parents are not well versed in the rituals. Can I do it even though they are alive? I found a simple ritual online but I intend to do it while omitting the parts for father, mother, and grandmother since they are still alive.
The reason why I would like to do it, besides honoring my ancestors, is because I believe the problems me and all my living kins ( parents, aunts, uncles, cousins etc.) face is because of Pitru Dosh.