Hi Chimo1,
Welcome and hello

This is a supportive place with lots of information and guidance from parents who have walked this path, too. I'm glad you found it, these aren't easy steps to take.
How old is your child?
Do you feel comfortable sharing the events that led to the diagnosis?
Is your child accepting the diagnosis, and receptive to treatment? What is her relationship like with you?
There are two very helpful books to get started, if you are looking for some reading material (and haven't found them yet). One is Loving Someone with BPD by Shari Manning, and the other is Overcoming BPD by Valerie Porr.
If your child is a teen, Blaise Aguirre's BPD in Adolescence is also excellent. He has some material on YouTube as well that is pretty good.
How are you doing, now that you have this diagnosis? It can be a mix of relief and fear for many parents. However you feel, this is a supportive community with parents who understand, and care.
LnL