A lot of stuff, such as Delves, heroic dungeons are locked until full launch while, Mythic+ Dungeons, raids, are locked until the season begins, which is the 10th of September.
Yes, professions will be unlocked, but if I remember correctly, there will be some recepes locked due to reagents from dungeons or raids (I might be wrong on this, but someone will need to confirm me on this.)
