I just had my ultrasound at 16 wiks 3 days and it says anterior placenta grade 1 pls. Explain further?

Placenta location. This is just stating for your doctor that your placenta is at the front (anterior) part of your uterus. The grading system reflects the age of the placenta. It will go from grade 1 to 2 and 3 as the pregnancy progresses.
Normal. This is just a description of the location of your placenta, which is normal. Grade 1 placentas are normal in early pregnancy. Nothing to worry about!