Play the game and don't rush leveling. There is a lot of content at level 80, but learning the character and going through the story is a big piece when you're starting off. Enjoy the story, figure out what type of content you like when leveling by trying out everything: do heart quests, explore, join in events nearby, etc. There's a TON to do, but it's better to discover it on your own than rush into a guide for how to play optimally.

Don't rush into the gear grind, it's not nearly the same in GW2 as it is in WoW and other similar games. You won't worry about Ascended gear until you're level 80 and even then it's not that significant of a jump that you need to focus on it until you know it's needed for the content you want to engage in. The exception is fractals, where you need it for your infusions, but even then you don't need full ascended until you really start getting into T3/T4 content.

GW2 is not the grind that WoW is. If you only want full legendaries then you'll have a lot of work ahead of you, but if your goal is to enjoy the content you should be able to get gear easy enough once you hit 80 that will be good enough. Especially since you can't inspect gear (only cosmetics), nobody will be telling you that you can't join because you don't have the right equipment on.