It's worth trying out a few different approaches without devoting too many hours to them at first to get a sense of what you find easiest, most enjoyable, and most profitable in terms of farming.

If you have gathering professions, an addon like GatherMate will almost certainly make it much easier to ensure that you never miss a herb or a mining node. GatherMate will remember the location of every herb and ore you collect, and it will display that information on both the mini-map and the world map, making gathering easier and more efficient.

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Gathering is a good way to get started making money. Finding resources to gather or mine while leveling your character is all that is required, especially if you are skilled in skinning. Make a mental note that you will not be able to pass the 225 skill mark in your professions until you are at least level 35.
One important point to remember is that you should always sell your gathered items at the auction house and make use of your bank alts to make the process as efficient as possible. In addition, you should look for long-term buyers for the mats; they are out there – just ask in the chat and keep your eyes peeled for them in the trade chat. This will help you maintain consistency in your sales while also saving you the time it takes to put mats on the AH.
Farming is more suitable for characters with a higher level of experience (level 40-50). Generally, farming revolves around instance runs, killing named bosses multiple times, running dungeons for the sake of getting a desired drop, and farming mobs in various locations and areas.
Dungeons and dragons
Naturally, the requirements of a perfect grinding spot are best met inside dungeons, where no outside interference is possible, and where you can be assured of receiving full respawns immediately after each reset of the dungeon. The only restriction is that you can only run 5 individual dungeon lockouts per hour before the game will no longer allow you to create new instances of the dungeon, so make sure to plan ahead of time.
Turn the Auction House on its Head
You can make a profit by purchasing an item and relisting it for a higher price at an auction house. It is possible to make a significant amount of World of Warcraft gold in a relatively short period of time by flipping Auction House items.
So you should spend every day scanning the auction house with some WoW Classic addons at the current price of enchanting materials at low prices (such as "strange dust"), and then checking the prices of the green items that people post for sale, which generate dust when they are disenchanted. In this mod, the best guess for each disenchantment is displayed. This method can be a convenient and quick way to obtain World of Warcraft gold.
Occupational Specializations
Professions are extremely important in WOW TBC classic gold, as they play a significant role in both earning money and providing much-needed items towards the end of the game. It is therefore recommended that you learn them as soon as possible, regardless of your intended use.
One of the quickest and most straightforward ways to earn additional gold is to learn some gathering professions as soon as possible – any two of Mining, Herbalism, and Skinning are suitable options.