Pissedoffdotcom - I wish you all the luck in the world, you’ll make a brilliant mum, and I’m so sorry becoming a parent hasn’t been easy for you.
My mum has said time and time again that she loved me exactly like any parent loved their child. The fact that she was never pregnant herself did not change that love. I have no doubt it will be the same for you.
She never thought to ask the surrogate about her family history because she saw me as her own child, but whilst it didn’t matter to her that we were unrelated, it mattered greatly to me.
Some people feel about a surrogate mother in a similar way as a biological mother, the person who carried them and gave birth to them may be considered a mother of sorts to them (or not).
If your child has questions, answer as honestly as you can in a way that is age appropriate. Let them know that it doesn’t hurt your feelings if they want to know more about their birth - it is absolutely their right and it is so natural to want to know where you came from, and your family history. It does not mean that they love you any less if they do want to learn more.
In that vein, please please please ask the surrogate as much as you can about her family history (not just her medical history). Even if she is a gestational surrogate with no biological connection to your child, it may still be important them.
My parents didn’t ask their surrogate about her family history. I have no idea what my grandparents names are, nor where her (and my) family came from. All I have is some photos and a name, and a google search that tells me that name is of either German or Jewish origin. I struggle with “not knowing” to this day.
Keep in (occasional) contact with your surrogate if possible, and let her become a part of your child’s family story. Even if it’s a letter once a year it is so important. This will not in any way threaten your relationship with your child.