Returning player with a single player question

Hi everyone, I’ve just come back to Hearthstone after a few years and for various reasons I ended up starting fresh with a new account. So really I’m just curious as to where all the old single player content went? (Like Naxx, dungeon run and the like) Do I need to unlock them somehow? Maybe they show up in the store every once in awhile? I’m just really sad I can’t jump back into them yet as they were probably my favorite thing to do in this game. Any insight into what happened would be greatly appreciated, thanks.

Kobolds and Catacombs, Knights of the Frozen Throne, Rastakhan’s Rumble, The Boomsday Project and The Witchwood adventures are all able to be claimed for free in the Battle.net shop

You should be able to buy all the adventures in the shop.

Wow thanks guys, I’ll be sure to go pick them up!

Some adventures, especially the free ones, can be claimed in the web shop, rather than the in-game shop, but isn’t one also required to unlock Wild in order to access those other adventures? Or is it just about Wild packs?