Welcome to Azeroth!
Glad to hear you’re enjoying yourself. 
Either you did your research, or someone has given you good advice; most new people don’t have the good information to roll their Horde on Drenor realm. You’re in the right place. Good for you! (For Alliance the usual realm to start on would be Silvermoon.)
And an aspiring gold-maker already. 
Time for me to roll out again my favourite how to start-the-AH video:
This is part 1 of a three-part tutorial that covers the very basics of how to make gold on the AH in WoW. Although it’s 6 years old, and some details have changed, and the markets are very different from the low-level herbs and the gems that used to be so reliable, it still covers the basic ideas and mechanics very well.
You can of course get started now. Your takings will be modest at low levels, probably in the low hundreds of gold, but more than enough for your limited needs. At low level you can sell transmog that drops for you - that is armour you get that is Bind on Equip (not Soulbound) so you can sell it to someone else, who then uses it and learns that armour appearance. This site will tell you appropriate prices to list at
https://theunderminejournal.com/#eu/draenor
but it costs you a deposit to list something in the AH, and you lose that deposit if it doesn’t sell. That’s not a big deal when you have lots of gold, but it could chip into your little pile quickly, so be careful and list only things likely to sell.
Have you got any addons yet? Addons are everywhere in WoW. If you are doing the AH, I strongly recommend you start with the addon Auctionator
https://www.curseforge.com/wow/addons/auctionator
There is a much more advanced addon Trade Skill Master, but I wouldn’t start you on that yet. You don’t need it for what you are doing, and it’s practically a whole college course just to learn it.
You can also sell low level herbs and ores and skins if you have those professions, but there isn’t a lot of gold in that now.
The real game of AH is to spot when something is priced low, buy it, and resell at a higher price, but that requires you to know what sells, so you need to know the patterns of your realm’s auctions.
When you get to max level, 120, you will be making much more gold from quests and drops, and you can farm gold by killing things in older dungeons and raids, and you can use the top level of professions. You will have a lot more gold, and a lot more ways to make it, and you can use that to make more. The sheer scale of gold you get at max level is very different. World quests you might do daily reward in the hundreds of gold.
In general, just follow the quests, and do dungeons if you enjoy them. There is no particularly better way to get to max level. Some ways are faster, but that is for people who have a dozen characters at max already and are just pushing through another. Just enjoy yourself!
When you get a little gold, buy a Netherweave Bag or two. They’re usually around 10 gold at the AH. The extra bag space is very handy.
Sites you should know
Wowhead.com for information about quests, items, and everything
Wowpedia.org for the story and characters of WoW
https://www.curseforge.com/wow/addons to get addons
https://www.icy-veins.com/wow/class-guides for the best way to build and play your class at max level. You have to adapt that for your level, since you don’t have all abilities yet.
And of course: if it’s in WoW, there’s probably a video on YouTube about it! You’d be surprised - I think there are individual videos for every quest in the game if you search.
Ask again if there’s anything else you want to know!
