I agree with what you are saying here: Every moment, experience and choice has led us here to this moment in life.

Personally I think every human grapples with regret, its very nature is that regret follows us whatever we choose.

However, I do try talking to my past self, not to tell them what not to do, but to integrate that past with my present and look to the Future. Perhaps you might like this story I wrote to my 15 year old self?

https://harshy-ugarte.medium.com/life-after-rebellion-an-open-letter-to-15-year-old-me-4b6b3ee30528