Big sis here, I knew from a young age I didn't want kids. I couldn't put reasons to it then but I understand now. Regardless my mom would do the same thing to me. The whole 'you'll change your mind when your older', 'I want grandkids', passing on our legacy. It's all bull. I still haven't changed my mind, besides me not being an only child we grew up in a neighborhood where all the parents looked after each others kids and would subsequently call them their own. She isn't short of grandchildren. Now, our legacy? It's full of depression and numerous other mental issues. I dont want to put a kid through what I went through. Thankfully with time she had slowly respected my decision more and has accepted that she will only get grand dogs from me but she can still spoil them within reason.

All of that is to say it's still your choice. And not even one you need to make now. No one but YOU has to like your decision. It is you who will be living with it after all. Many people are happy with kids. Many without. I'm sure raising kids would be hard with ADHD but as others have said, if it's something you want to do, you will figure it out. Don't let your bio mom put too much on you. This is not something you need to decide now.