Here's a list of helpful tips and tricks for starting out your adventuring career in Path of Exile:
You have flasks that fill with health or mana liquid when you kill monsters or return to town. It is important to watch your flask levels carefully when you're in a heated fight.
Items can be traded to shopkeepers in exchange for items that serve as currency. POE Currency is usually various POE Orbs, such as Exalted Orb, POE Chaos Orb, etc. It is used to players Trade Items, Strengthens Equipment, Skill Gems, etc. Only when players have enough Path of Exile currency can have better gaming experience. However, in many cases, the player's POE currency is not enough, so they can use various methods to get the required POE currency. Such as buy poe currency online.
Make sure to fight enemies in chokepoints. This plays more like olde ArRPG entries where you are not godly and actually have to fight a few enemies at a time. Playing this like your modern ARPG will get you killed in a hurry.
PoE has a League system where you can create a character in special conditions. For example, you might make a character in a Player vs Player League or a Hardcore League where you have only one life. Characters in special leagues that get booted out of said leagues (in the Hardcore league you will get booted out for dying) will end up in a Default league (this is where your character ends up if you don't choose a special league at character creation).
While this game can be played solo, don't forget the online component. The community is pretty helpful. If you don't want to ask in-game, you can always use the official game forums to voice your doubts and concerns as well.