Probably wouldn't help in practice.
At the end of the day, the choices you make are as a result of your circumstances rather than your knowledge.
But you'll be repeating your circumstances hence make small different decisions. The biggest regreat was when i was 19 and didn't take a certain offer and had a great cpuple of months with someone. Most of the changes would be with girls and not be so uptight and have more fun. Also choose different subjects in my A-Levels and get better grades
And foreknowledge might even make things worse for you.
Anybody remember the TNG episode where Q does just this to Picard and it turns out to be a poison chalice?
I don't believe that