Hi my Coombs test is positive what I have to do? What is the next step?

Let me explain. The direct coombs test is used to test for autoimmune hemolytic anemia; ie, a condition of a low count of red blood cells (aka rbcs) caused by immune system lysis or breaking of rbc membranes causing rbc destruction. Follow hematologist direction for the treatment and precautions.
See a hematologist. You should see a hematologist for evaluation and see if treatment is needed.