As it is in the title of the series, the titular Dragon Balls always play a major role in most everything associated with it. This extends to Dragon Ball Z: Kakarot as well, where the Dragon Balls play a major role. You do not have immediate access to them outside of story segments until a certain point of the game, so this guide will explain when you will be able to start searching for them and collect them to eventually summon the all powerful Shenron.
How To Find Dragon Balls
Through the first couple arcs of Dragon Ball Z: Kakarot, specifically Attack of the Saiyans and Evil Emperor Frieza, the Dragon Balls play a major part of the story with the revival of Goku, Piccolo, and much more. However, you are not able to just go around and hunt for the Dragon Balls to use at your leisure during these times. Instead, you will have to wait until you have completed the Evil Emperor Frieza arc and have returned home to Earth.
While you are in the intermission section before the Android Terror Arrives arc begins, Chi Chi will tell you about going to try and collect the Dragon Balls. Starting from this point forward, the Dragon Balls will be available to you to find whenever you are navigating the semi-open world found in Dragon Ball Z: Kakarot.
At this point, anytime you go to an area where a Dragon Ball is located, an icon will appear on the map to let you know. This serves as essentially your Dragon Radar, allowing you to find each of the seven Dragon Balls after they are scattered around. Once you summon Shenron and make a wish, you must wait 20 minutes for the Dragon Balls to appear around the world again. Once this happens, rinse and repeat the same process as before to summon forth Shenron yet again.