Yeah, wrong forum, but that is ok. Mods will move it eventually. As of right now all currently released DLC is free. However, the season pass will give you the 3 big DLCs that will cost money as they release. If you have the Season pass then you should be fine.
As for advice. Start on a lower difficulty, and learn what abilities do. Learn what your Attributes effect. EG might = damage and healing, but also increases your fortitude saves. High Fortitude makes spells that target fortitude less likely to hit. Might and Con boost Fortitude. Perception and Dex boost Reflex. Intellect and Resolve boost Will. Then the 4th save is Deflection which protects you from weapon attacks. Fortitude tends to protect from poisons and the like. reflex protects from fireballs and stuff like that. Will protects from mental debuffs and charms. Once you learn this stuff you learn to manipulate your saves to make yourself more sturdy, or manipulate the enemy's saves to ensure that the big spell/ability you are going to use has a higher chance to hit/crit.
So, to recap, learn Deflection, Will, Fortitude, and Reflex. If an enemy attacks you it will be their accuracy vs one of those 4.
Another form of protection is Armor Rating which works similar to Damage Reduction. Penetration counter acts AR.
Hover your cursor over an enemy to see what their saves, AR, and immunities are. Hit them with stuff that attacks their weaknesses. For example, youre fighting an Ogre. If you hover the Ogre you see that his Fortitude is sky high, but his reflex and will are fairly low. Use abilities that attack reflex or will. Try to attack the lowest save. Sometimes you will have to attack the second best option, and sometimes you just have to hope what you have hits.
Anyway, in game there is a hyperlink system that will let you hover this stuff and read up. Don't be shy about getting your learn on. It can be overwhelming at first. Once you get the basics down then all will be well.