My thyroid gland is enlarged and i hv tsh 5.76 and tpo 5.91 iu. what does it mean? what medicie should i take? do i need surgery for enlargd gland?

Thyroid enlarged: Is that TPO high? The normal range varies with the lab. It sounds like you have Hashimoto's thyroiditis. Unless there is a predominant nodule that is suspicious looking, you need to take levothyroxine and you don't need much of anything else. The thyroid may shrink in time, but may stay large, but there is likely no need for surgery. See an Endocrinologist.