How do I plan builds and progression?

Hi guys I'm playing WoW for like the first time, going in completely blind. I've played like 2-3 mmorpgs before but nothing too complicated. My issue is I'm really confused with how progression works for this game haha
I was trying to get a specific axe called WhirlWind Axe which most guides online said was in WotLk but I couldn't even find the quest to get berserker stance? I don't know if I'm doing something dumb or if I'm looking up guides for the wrong version xD

Then I gave up on that and decided to get this axe called "Fiery War Axe"
So I checked this wiki https://wotlk.evowow.com/?item=870 and it said it dropped from IronJaw basilisks, which I farmed for an hour
Then I realized the drop rates weren't making sense since the 2.5% junk item I kept on getting, and then I got some items which weren't even on the loot pool
So I'm really confused on how I can know what drops what and where to get specific skills like berserker stance

tl:dr
I can't find a reliable wiki to plan for gear and progression, idk if I'm being dumb and checking older / diff vers or if one just straight up doesn't exist
Help appreciated

Try to revisit starting zone, 2nd settlement and homecity warrior trainer to start berserking quest, one of them should send you to place.

And about items/builds, before 80 it doesnt matter. Wow s charm is being blind for the first time, you wont experience it again. My advice is to forget guides, dont chase items and be happy with whatever you get.

As Bartardbottle said, leave the item grind behind you and focus on leveling.
To farm a lvl 35 weapon with a 0,07% drop chance by killing the same mobs again and again it's not only a waste of your time but also a short way to boredom.
When you will reach higher levels, you will replace that weapon with a quest reward or with an item dropped in a random dungeon (assuming you are joining rdf while leveling, since it's your first time in WoW).

As for the Berserker Stance chain quest, any warrior trainer in any major city of your faction (Thunder Bluff, Orgrimmar or Undercity if you play horde side, Stormwind, Ironforge or Darnassus on alliance side) should give you the quest "The Islander" as soon as you reach lvl 30.
The quest will lead you to an island on the eastern coast of the Barrens (yes, it's harder to reach that place if you play alliance, because the Barrens are horde territory but you just need to stay away from guards and villages).
On that island you will need to complete a second quest, a short but funny challenge: you will need to defeat a serie of opponents in a small ring.

Good luck, have fun.