After the liquid iron therapy for my baby boy, is it gonna b back to normal? (he has 10.6 hb level in his CBC so doctor gave me liquid iron (feroglobin medicine) 3.5 ml for 3 months)?

Anemia. Yes he should do very well. He has only mild anemia. Your doctor will likely check it again after treatment. Pretty common . That is why we check it.
Should. This is a common approach to mild anemia which the level shows. It is most often from iron deficiency & a supplement usually fixes it. If the kid inherited a thalassemia gene & has thalassemia minor that would also produce small red cells & that hemoglobin level. The level would not change much with iron treatment. Later testing will sort that out.