With protein in my urine, do i have to eat less protein? if yes i should not eat ocean fish, in which case i have to supplement with omega-3 fish oil?

None of the above.: Protein in urine has a multitude of causes and can vary from small amounts to truly large amounts. Treatment of your proteinuria should be directed at the cause of the proteinuria not the proteinuria per se. Protein intake may be modified depending upon your condition but this is not generally required. You should not change your protein intake without discussing with your doc.