I have had 7 back surgeries, I am fused from t–10 to s–1, I just found out I'm pregnant. Is it possible to carry the baby to term?

Yes. There should be no issue other than getting an epidural possibly.
Sure. It will be likely be uncomfortable i suspect but possible , you will have to avoid some meds as well, t4-l4 a classic fusion for scoliosis have carried many to term it might be fine you dont have any lumbar motion to blame . Ive had one similar paitient she had a baby and subsequently brought the child to office on follow up vists the child seemed to make it all worth it.