Decided to do this on my own

I have been pondering myself and who I am recently. In doing so, I have realized I am Demisexual. But I have wanted to become a mother since I was young. So I am trying to conceive with the help of a acquaintances and raise the baby alone. This makes me happy but also very nervous. I know my parents will be happy to hear that they will finally be grandparents, but only my mom know about my bring demi. I'm not really sure how to being it up to my dad.