1. Head to Ecruteak City: Your next goal is to travel to Ecruteak City, which is located to the north. You'll pass through the Ilex Forest, where you can find the Slowpoke Well and the legendary Raikou (if you chose Cyndaquil as your starter).
2. Train your Pokemon: Whitney's Miltank is a tough opponent, so take this opportunity to level up your Pokemon and prepare for the next Gym Leader, Morty.
3. Explore the areas around Goldenrod: There's a lot to explore around Goldenrod City! You can:
* Visit the Goldenrod Department Store to buy items and learn about the Move Tutor.
* Take a trip to the Goldenrod Radio Tower to find Team Rocket and a very special Pokemon!
* Explore the Goldenrod Underground, a large cave system home to various Pokemon and items.
4. Visit the Day Care Center: This is located in the north of Goldenrod City and can help you level up your Pokemon.
5. Catch Pokemon: There are various Pokemon to catch in the surrounding areas, like Snubbull in the Ilex Forest, and Pidgey and Rattata in the open fields.
6. Prepare for Morty: The next Gym Leader, Morty, is a Ghost-type specialist. Consider catching a Ghost-type Pokemon yourself or training your Pokemon with moves that are strong against Ghost-types.
Remember to explore, train, and collect items. This will help you prepare for the challenging battles that lie ahead!