The Souls games have a few mechanical idiosyncrasies that can trip you up if you come in with assumptions based on other RPGs.
Equipment progression works differently in Souls games than in your standard ARPGs. New gear provides mostly horizontal progression, in that different weapons have different movesets and characteristics like weight, reach, and attack speed which lend themselves to different playstyles. However, for the most part one weapon isn't much better than another in an absolute sense. Vertical progression comes mostly from upgrading weapons at the blacksmith rather than getting new weapons.
Accordingly, once you find a weapon you like, upgrade it early and often. Armor can also be upgraded but the value of doing so is pretty low. Don't worry about running out of upgrade materials, you'll end up with plenty.
When raising attributes at level up, focus on those attributes that work well with the type of weapons you use. Weapons have certain attribute requirements, but they also have attribute scaling, which mean that damage from that weapon increases with that attribute. Heavy weapons have higher Strength requirements and scaling, while lighter weapons have Dexterity requirements and scaling, as you might expect.
If you're not using magic (and you don't have to use magic at all in any Souls game), then Attunement, Faith, and Intelligence are all dump attributes which you can safely ignore. It's easy to play a Souls game without ever using magic, and basically impossible to play one without ever engaging in melee combat. Magic can be fun to use, but if you're feeling overwhelmed with options it's an easy thing to drop.
If you're ever unsure about what a stat does, look it up on a wiki. Seriously. There's a ton of info that goes unexplained in the tooltips. For instance, the agility stat determines how long you are invincible while rolling, so unless you play as a tanky character you'll probably want to put some points into an attribute that boosts agility (figuring out which attributes do this is a useful exercise!).
