I am not sure whether to believe in re-incarnation. Granted that there might be Poincare recurrence for the entire universe, and if that is the case I am pretty sure the Boltzmann brains might expedite the recurrence, but still there is no evidence how everything might avoid heat death.
So to work with what is before us, we have to emulate the groundhog day within the constraints of reality. Not everything repeats exactly like in the Groundhog Day. There are patterns that repeat which can be learned from and improved on. Patterns of human behavior for instance. Lessons can be learned. Not all mistakes can be undone. At least they will remain part of the memories of those who were grieved.
I feel like a piece of the universe has just woken up and is alive before it sleeps for a long time, never to know whether I will be woken up again. And if I ever wake up again, I wouldn’t know what happened the last time.
So all I can learn from is experience while I last and while I can hold memories. Everyday can be learned from. It is never exactly like the previous day, and even if it is all repetition of eons, due to lack of memory, there is nothing to be gained by the knowledge of future.