Like Winged Keys, Gold is another important currency that you will be able to acquire throughout the course of your playthrough in Harry Potter Quidditch Champions. This currency is primarily needed to purchase cosmetics from the in-game shop.
You will not be able to get your hands on more Gold by investing real-life money. The only way to earn it will be to complete some of the in-game challenges and progress through the career mode.
Here is a guide on how you can get more Gold in Harry Potter Quidditch Champions.
Best ways of farming Gold in Harry Potter Quidditch Champions

Here are some of the best ways of getting more Gold fast in Harry Potter Quidditch Champions:
1) Complete different stages of the Career mode
The most reliable way of getting more Gold in the title will be to complete the main narrative of Quidditch Champions. As you make your way through the various Career levels you will increase your fame and earn some Gold each time you level up.
So once you keep making your way up the school Quidditch ladder in Hogwarts, you will be able to consistently farm and accumulate Gold.
2) Complete Daily and Weekly Challenges
Gold is also something that you will unlock as a reward by unlocking some of the tiers in the seasonal rewards track. This season pass is free for everyone and you will be able to level it up by completing the various Daily and Weekly challenges that refresh in regular intervals. You can complete the challenges by completing the campaign as well as PvP matches.

3) Complete the Career challenges
Career challenges are permanent missions that do not reset. These consist of Dedication and Mastery challenges that you will be able to complete by taking up some role-specific missions. These challenges are pretty difficult to go through, but once you complete them you will earn approximately 400-700 Gold quite easily.
4) Purchase the Deluxe edition
If you have access to the Deluxe Edition of Harry Potter Quidditch Champions you will automatically obtain 2,000 Gold.
How to use Gold in Harry Potter Quidditch Champions

The best use of Gold in the game will be to purchase cosmetics with it in the in-game shop. You can also buy headgear, brooms, and Heroes of Hogwarts skins like that of Hermione Granger along with Fred and George Weasley.
As there are no microtransactions in Harry Potter Quidditch Champions, Gold will be the only way of obtaining some of the items from the shop.