If i turn my eyes to the corner (up, left, down, right) without turning my head i can faintly see 2 big dark spots in center. what is that?

Get checked: If the spots are not moving (like "floaters"), then they may be due to a number of possible causes including damage to your cornea. You should discuss this with your primary medical provider or specialist, & may need an ophthalmology evaluation. Hope that helps.

Visual Field Defect: Something in your visual field is a concern, that needs proper examination by an eye doctor. People with hypertension, diabetes, sickle cell, herpes zoster/previous shingles and many more, who xperience this needs urgent eye evaluation.