Hey everyone I’ve been playing Wow on and off for about a year now and I have the issue of not really knowing what to do once I reach level cap. My first time leveling to cap was in shadowlands and I enjoyed the questing in BFA and Shadowlands. Unfortunately once I hit level 60, I kind of just quit. Now that dragon flight is out, I can now level up to level 70. I’m looking forward to it, but I feel as though I am going to run into the same issue.
Dat loot grind! 
But the trick is to find what you enjoy. There is more than enough quests to max level in Dragonflight and have a ton left. Some other ideas:
Max reputation
PVP
Mythics
Raid
Craft master
Transmog master
There’s also achievements such as Lore Master (doing all the quests), mount/pet collecting, world quests and events, and a ton of other stuff you can do solo if group content isn’t your thing.
There are several things you can do after you hit max level. What I would recommend is doing the dungeon quests you can obtain in Valdrakken to get you some valuable items to help you do better in dungeons and on world quests. When you can obtain loot from a world quest that can help you in dungeons also. Use the looking for group tool to do random dungeons for a while to get a feel for them.
Id highly recommend RANDOM Battlegrounds!
Save up the honor points you get, Buy some PvP gear with it - Trinkets first for the set bonus,And eventually you will save up enough conquest to buy the MAX level pvp gear you can use open world and in PvP. The maps are fun and highly re-playable. Its the avenue of the game that is played for the EXPERIENCE, not the Reward. (Because the best gear for it is purchased through just earning conquest which you do passively)