I need to find out some knowledge if anyone can help me Questions

I’m currently in the middle of getting my first puppy! A little staffy! He’s currently 8 days old but will be getting him at 8 weeks.
The breeders have just informed me that dad is a full staff, and mum is a staff with dobermen bloodline somewhere, as the mum of the pups mum is 3/4 staff and 1/4 dobermen, I’m worried if my little staffy pup will be grow to be a massive dog like a dobermen? Or will he likely be full staff?
I can’t seem to find anything on the internet for this so I hope someone can help me.

It's impossible to predict the exact traits inherited by mixed-breeds, but if you’re that worried it would be advisable to go to a reputable breeder, who also does relevant health tests.

Have you see the parents of your puppy?
Assuming that you have, and they both look to be a normal Staffy size, I think your puppy is unlikely to grow to Doberman size - maybe just be a little higher on the leg. Make sure that you see at least the mother though, people will always tell you what they think you want to hear.

Hi, I have seen dad and mum, dad is full staff and mum has dobermen ears what it looks like but still looks fairly like a staff.

Mum is white one.