A hawk could likely pickup a 1 year old or smaller baby or even a kid under 8 years old but no adult human.
A hawk could not lift the weight of a teenager or a full grown adult human as that would be too much weight for the hawk to be able to lift.
But if you have a small toddler such as a 4 year old or 3 year or 2 year old and the hawk decides to take off with your child then it could be possible for the hawk to take off with them.
Even a 5 or 7 year old child a hawk might be able to lift and take off with them but they could not lift a human adult.
Hawks can take off with chickens though especially the chicken hawk so if you have chickens and there are hawks in your area make sure to keep a top over the chicken coop to keep hawks out.
If you have small children and there are hawks about make sure to really keep an eye on them which you should be doing anyway.