I don't think you can give her any advice on her future life. Seriously, you have no clue what she might be going through when she's 16, and little you can say now will be relevant to her. You don't want to leave her with a legacy of useless advice.
Instead, do what my father in law did - he was in much the same position as you when his grandkids were being born. He knew he would not live to see them get out of diapers.
So he spent the last 2-3 years of his life documenting his life and family history, with photos and personal stories of failure, loss, success, joys, sorrows, and tributes.
Those 3 albums are an incredible insight into his life, and the life of his family that would otherwise be lost. It's a great document that will let your daughter get to know you when you're gone. It's an unbelievable gift he left us.