If you are lost in terms of what to do, it strongly depends on what type of player you are (here is the article which explains classifications and you can check what you are: https://en.wikipedia.org/wiki/Bartle_taxonomy_of_player_types). Nice thing about GW2 is that it caters for all player types so it's just a matter of trying things out and figuring out which content fits you.
If you are more of a Killer - try PVP content, Conquest is adrenaline rich while WvW provides good mix if you prefer variety.
If you are Socialiser - join a guild, there are plenty of friendly ones. WvW also offer opportunities for casual grouping. Or get to 80 and join Events (https://wiki.guildwars2.com/wiki/Event_timers). Wander randomly around maps and join events.
Look for Commander icons ("apple" or colored icons on map) or use Looking For Group section. Join their squad, go hunt something together. With ranged weapons, it is pretty safe and fun to join Bounty hunts.
Get into Expansion maps and join the Meta events (e.g. Auric basin or Drizzlewood are super fun). They also offer great opportunity for role-playing. If you have not opened some map, the trick is to check Looking for Group, joining and group and then using "Teleport to a Friend" utility to teleport to the Commander. After that the map is open forever.
Check the skins/dyes/outfits. You can buy them or get them some through achievements/chests.
If you are an Achiever - get to 80, one of the fastest ways is via Personal story. And then:
Collect Hero points, train all skills and traits.
Get a specialization. Learn it well - that's one of the hardest but also most rewarding aspects of Guild wars, the way you play your class impacts your success but also contributes to fun when it starts working like a clockwork and you can solo something challenging
Build your gear - these websites offer starter templates: https://metabattle.com/wiki/MetaBattle_Wiki, https://discretize.eu/builds, and this one allows your to create a build with gear before committing to it in the game: http://en.gw2skills.net/. Gear is important past 80 but don't try to go for Ascended initially, Exotic is just fine. You can craft your gear, or focus on gathering/crafting something else/selling/buying gear for yourself
Visit maps and try to complete some, or collect Mastery points and gain some expansion specific skills (since you do have expansions).
And of course - look at the Achievements panel, Daily achievements or near completion, or focused on some specific gear or class.
Get mounts - they are extremely fun (start with Raptor and Glider), and later ones require time. All mounts start with a specific expansion story step - Wiki tells you which step is required. Simply jump to that step in your character story screen, or follow the story from the Step 1 until you get there organically. As some mention, for Raptor just start Path of Fire, and for Glider https://wiki.guildwars2.com/wiki/Glider_Basics - https://wiki.guildwars2.com/wiki/Establishing_a_Foothold
Learn crafting and get as far as you can (getting to the end initially would be hard without materials and gold)
Join Meta events - usually on expansion maps. Look for map talk or check https://wiki.guildwars2.com/wiki/Main_Page or look for Commander. They are extremely fun and rewarding.
Get into Fractals, build ascended gear
If you are an Explorer - explore!
Follow the personal story - this will bring you to many maps but you'll only touch a few small parts. Try completing them, or follow the gates to the nearby maps. There are some astonishing terrains in GW2, beautifully detailed areas, some hidden gems or architecture or landscaping. Open all points, portals, vistas, hearts, loot the chests, do the puzzles. Get a mount before going too far - they help you get faster and get around tough terrain.
Try different classes. Usually it takes a few classes to find the one you like playing, they are all vastly different. For Ranger, you can try collecting different Pets
Go for the expansion maps - try completing expansion stories, or just open them up and join the Meta events. You'll go into some new places, face new challenges and get some good rewards.
Go into Fractals
You can do some of these before 80 but you level so fast in GW2 that initially just set the goal of getting to 80 and enjoy some of these on the way. After that - just try different things, literally, tick them off the list until something clicks.
Feel free to message me directly if you have more questions. Cheers.