After you meet Roark in the Oreburgh Mine, he goes back to the Oreburgh Gym, where you can challenge him for the Gym Badge.
You can skip this battle by going up the stairs, but if you decide to battle Youngster Johnathon, he has a level 10 Geodude. You get 440 Pokédollars for winning.
You can skip this battle by going up the stairs, but if you decide to battle Youngster Darius, he has a level 8 Geodude and a level 8 Onix. You get 416 Pokédollars for winning.
Gym Leader Roark
Go north and talk to Roark. After some dialogue, the battle will begin. He has Potions that he may use during the battle. He has a level 12 Geodude, a level 12 Onix, and a level 14 Cranidos.
You get 1960 Pokédollars for winning, and the Coal Badge is added to your Trainer Card. You will now be able to use Rock Smash outside of battle using your Pokétch. You don't need to teach Rock Smash to a pokémon to use Rock Smash in the field. He will also give you some TM76s, which will teach pokémon Stealth Rock.
You will also get the Stickers that Roark uses.
The Global Club in the basement of the Pokémon Center is now open. If you go there, Teala will explain how it works. You can talk to the people at the counter on the left to enter the Union Room. You will need to link a Nintendo Account to use the Global Club features.
New Poké Mart Items
Now that you have a Gym Badge, the Poké Mart will now be selling a wider variety of items.
Meet Your Friend
Go west toward Oreburgh Gate, and your friend will bump into you. He is going to Jubilife City in order to reach Eterna City.
Oreburgh Gate B1F
Go west from Oreburgh City to enter the Oreburgh Gate Cave. Now that you can use Rock Smash outside of battle, you can check on the brown rocks in the cave to break them. This allows you to go north in the cave. The path leads to some stairs. Go down them.
In this area of the cave, you can catch Geodude, Psyduck, and Zubat, and you can use the Old Rod to catch Magikarp.
In the east side of the area, there is a TM70 Flash. In the west side, there is a bag of Stardust. There are no more items that you can reach yet, so just leave the cave (you can use an Escape Rope if you have one).
Back to Jubilife City
Go west through the cave until you reach Route 203, then go west through the route to reach Jubilife City.
Team Galactic Grunt Battle
Go north and you will find Rowan and Dawn or Lucas dealing with two Team Galactic Grunts. You and Dawn or Lucas will battle them together. They have a level 9 Wurmple and a level 9 Zubat. You get 1296 Pokédollars for winning.
Gifts from Bebe
Bebe will arrive and give you access to Pokémon Boxes from anywhere. Just choose Pokémon from the X menu and press R to access your boxes. Bebe will also give you Ball Capsules. This lets you use the Capsule Decoration feature from the Ball Capsules menu, which is added to the X menu.
Jubilife TV Station
Now that you have defeated the two Grunts in Jubilife City, you can now enter the Jubilife TV Station. You can talk to the person at the front desk to enter the Pokémon Loto once a day. You can talk to the person to the left of the counter on the first floor to battle. A different trainer will be there each day. On the second floor, talk to someone to get 3 Bubble Stickers B. On the third floor, you can see the Ball Capsule stickers used by the Gym Leaders that you have defeated so far. The fourth floor has ranking rooms to rank your local and global groups. You can talk to someone on the third floor and choose "EVERYONE HAPPY WI-FI CONNECTION" to unlock Mystery Gifts. Talk to them again to get stickers.
Now that you have dealt with the Team Galactic Grunts and talked to Bebe, you can go north to Route 204.