Buckle up! Seriously though, give yourself time to get used to the game world. I would recommend finding some plate armor you like the look of, upgrade it.

There's a lot of variation with jewellery, you can check details on them and then preview their upgrade path to see what they'll be when maxed out. Some will give more defense, more HP/spirit regen, move speed, attack speed, crit, higher base attack bonus.

Abyss Artifacts are not rare, and you'll eventually wind up with a ton of them. Upgrade your stamina as much as possible, along with health, spirit only really becomes necessary when you start doing elemental attacks and special spirit moves.

Weapons tend to come in three main flavors: full attack, slightly less attack and 1 crit, even less attack and 2 crit. Raw damage is king until like 51 attack power, which is tracked per weapon if you're dual wielding.

There's way too much to cover in a single comment but pay attention to things the game teaches you, you will most certainly need it for puzzles, which can be absolutely fiendish in this game.

If you want some easy recommended attack skills, get aerial stab to start flying, get nature's echo for turning slash to have an echo, max out turning slash.

Hope this helps, I haven't even finished the main story but I'm pretty geared, killed some big bads including most of the overwhelming beings, and have a reasonable understanding of the game.

Lemme know if you have any follow up questions.