First time Istanbul

Hi from Sarajevo., I am coming from 26th til 30th of march first time in my life in Istanbul with my friend, we booked paris hotel Protected content from Blu mosque.. so if there is anyting to raccomand to go see do in this days.. we just want to have relaxing stay and enjoy not running arround as all tourists, it is impossible to see all so we will se what is arround and try to really enjoy our staying there