Hey there.
It’s not worth bringing your main over, unless you are 100% sure about it.
There are a few raiding guilds on AD that have roleplayers in them:
Anyways, it would be a good call to just install TRP3 and have a look around in a hub like Stormwind to see if you like it. Leveling up has never been easier and quicker.
Never go to that accursed place, it’s not a good place for roleplay.
Try Stormwind.
Yes, have a look through the forums. There are countless guilds (many even not listed in the forums) and even realmwide events. Guild events of course too.
Here’s my suggestion:
keep your main on your current realm. Create a level 1 (or so) character with a basic TRP3 profile and walk around Stormwind. Level that level 1 character up and see if you do like it all. Then you can still think about transfering your main over.