28 weeks pg-just left 8 weeks @hospital for 0 cervical length/funneled to cerclage/iu. Shocked to still be pg! Could I go full term? On procardia/steroids

Yes. You could, but you are a high risk to have a preterm delivery. Every day you keep the baby undelivered helps the baby when the baby eventually delivers. Good luck!
Not likely. Your history puts you at very high risk for preterm birth. Are you taking vaginal Progesterone nightly already? Good luck with your pregnancy and stay close to your hospital until delivery. Bed rest may be a reasonable albeit unproven precaution. I would certainly avoid working or studying until delivery if i were you.