No, you won’t. Not necessarily. There is a better way these days.
The game has changed. You no longer need to do Loremaster on one character. And you can go to any expansion at Level 10 with Chromie Time.
Achievements are shared account-wide.
You can the achievement for Quests for a zone on one character, say Grizzly Hills Quests, and for another zone on another character, say Borean Tundra Quests, and another zone on a third character, say Icecrown Quests, and they all add up towards your Loremaster of Northrend.
Or you can do Loremaster of Outland on one character, and Loremaster of Northrend on another, and they still count for both.
The way to approach questing for you is to make one character for each expansion. Make one for TBC, one for Wrath, one for Cata, and so on. Different classes, different races, Get each character to 10, then talk to Chromie and go to their expansion. You will still get your Loremaster, but you will also get a whole set of alts at level 70 or 80 you can choose from in the process.
While you will overlevel each expansion in the process, that will happen only near the end, so the amount of miserable one-shotting experience will be minimised.
Loremaster for EK and Kalimdor is a bit different. Their zones never scale above 30, so any character that gets to 35 is in one-shot mode. And they have a LOT of zones. You could make a bunch of characters and level them to 30, and/or you could suffer the Godmode experience.
So your plan is:
First character: You will probably be forced to start in Exile’s Reach, which I call Cardboard Island. OK, so pick a class, maybe use that Warrior you posted on.
Pick an expansion. I would pick Dragonflight. It is a good questing experience. It’s pretty weak story, and some bad characterisation, but the process is good and you get your mount nicely. Quest through it, following at least the featured quests, the ones with the brown shield around the exclamation mark.
That will level you, and bring you through the full story.
Once you get a character to 70, you are no longer locked to Exile’s Reachm and can choose your racial starting zone thereafter, for future characters. And I recommend you do, for the background and character flavor.
Then make, say, an Undead Warlock, level to 10 in Tirisfal Glades, and choose another expansion at Chromie, maybe Wrath.
Keep doing that, and you won’t regret your time seeing the world -and youwill have learned all the classes and have a flavor of the races, and youwill have all these characters to choose from.
I really recommend against it. I do in general, but especially for you, with your Loremaster aspirations.
We regularly see people who have taken the TWW Book Tour left in a limbo state because of bugs and glitches and inconsistent phasing, and unable to start the real campaign for the expansion,
Addons are in flux. Blizzard has declared war on combat addons recently, and most of those have been removed or neutered.
If you are inclined towards completionism in any sphere, I hightly recommend
Altoholic to keep track of your characters and
AllTheThings to keep track of what you have done and have yet to do.
Auctionator helps a lot with teh Auction House.
Personally, I very much like Bartender4, to make managing buttons and bars easier.
I would suggest searching YouTube for RECENT videos recommending specific addons. Look at them, see whether you think you would like them. Given the recent changes,any addon morethan three months old may be giving you out of date advice. Start with just a few, and add more as you fine a need for them.
Wowhead for quests, items, NPCs
Icy-Veins for how to play your class
and this video
It’s a year old now, and a little out of date. It is massively long, but broken into 1-2 minute chapters, and you get a Table of Contents when you view “more” to see the full description.
Do PLEASE ask again if you have any more questions or want any more detail.