What I know now.
I would make different mistakes.
It is easy to sit back and second-guess your decisions. We each know so much more about the situation than we did when it happened. We see the dynamics of the exchange. The consequences are clear. The long-term results have been experienced.
So maybe you would make that one decision better. But then you would experience the same lack of knowledge about other things. And you would simply make a different poor choice.
There is no use in replaying the past in your mind and thinking about all the ways you would do life differently. It is only helpful to work on the future carefully. To take all of your wisdom and apply it to today’s choices.
Then one day, you can look back on what happened now and be happy with all you have done.