A bit of advice...
The only constant is change. Every year I get to know myself a little better, but even as I get acquainted with that version of me I know I'll be growing into somebody different. It's hard to accept at any time that we won't necessarily always like the same type of food, the same music, or keep the same friends as the ones we have now. There are some things in life that we commit ourselves to wholly, willingly, only to find that they are hindering our own growth, or moving away from us as inexorably as continental drift. One of the hardest lessons can be learning to let go, or choosing to hold on in spite of the increased strain.
As long as we are alive, we are evolving - and unlike Pokémon, we have no final form to aspire to, only various stages of being. With increased age, we have improved perspective on everything that has come before in our personal timelines, and I doubt there are many people who don't wish they could impart some of their present wisdom (or bitter experience) to their younger selves.
But would you have even listened???
I don't think I would have. Anyone who knows me well has seen me go through some tumultuous life changes during the last half a decade, and I won't lie and say that any of it was easy. There have been losses, but there have been significant gains - not least a better understanding of my own heart and what really matters to me.
It sounds glib, but there it is! I look back on the things I was prioritising, the hedonistic indulgences that made me "happy", and I can see how little any of it really meant. I know that the past me was a lot of fun, crazy, and morbidly interesting to those tuning in to watch the inevitable train-wreck of her life, but the present version doesn't mind being less shiny. She's happier, healthier and her hair is way quicker to wash now.
I can't change the past, and it's an important part of who I've become - someone who can look back and laugh at her own strange behavior. In another five years or so I could be shaking my head at the memory of what I'm doing now, but hopefully without too much regret. Change isn't just possible, it's inevitable, so aim to grow into somebody you can love - even after all the dumb stuff they've done. That's my advice, and feel free to ignore it - I certainly would have.