It is important that you don’t censor yourself in this writing activity. It is just for you (unless you want to share it in the comments). Try to write freely, do not filter your thoughts, just get them all down. You can always redraft later.
Write a Letter to your Younger Self.
Write a letter to yourself at a younger age, it could be your child-self or the person you were just a few years or decades ago.
You can offer compassion, forgiveness, advice, whatever you feel comes through.
It helps if you try to imagine the younger self you are writing to as a different person.
In the comments below maybe you would like to share the core message of your letter.