You get a total of 49 skill points to distribute normally. You can get 2 more using the "all skilled up" talent and six more buying the book from the Teller of Secrets and finding one book. So ideally that gives you 57 points. So in an ideal situation you can max out three skills {45) and have some points left over for other skills (4-12). That is why gear becomes important if you are going that route. Many players focus on just two skills to max and spread the remaining points into skills they want to roleplay, e.g. crafting, smithing.

As for attribute points get the main attributes of the character up to ten initially then from the wiki:


Divinity Wiki

All Attributes start at base 5. A newly created character has five Attribute points to spend. Each even level grants an additional Attribute point, ending up with 15 spendable Attribute Points.

There have been some changes in Attribues from DOS to DOS:EE.


Effects
Strength
20 Carry Weight per point (base 10)
6 Offense Rating per point for Strength-based Weapons
Every 5 strength points after 10 STR reduces the cooldown of Man-at-Arms by 1 turn
Dexterity
2 Defense rating per point (or -2 per point) **See derived Stats as this can go negative
6 Offense Rating per point for Dexterity-Based Weapons
Intelligence
Every 2 intelligence points after 4 int reduces the cooldown of magic school skills by 1 turn
6 Offense Rating per point for Intelligence-Based Weapons
Constitution
1 Maximum Action Points per point
6.2 Vitality per point and level (+7.13 in normal difficulty due to the +15% bonus)
Speed
0.1 Movement per point.
0.5 Initiative per point.
0.5 Turn Action Points per point.
0.5 Start Action points per point.
Perception
1 Hearing per point, No Longer Grants Sight (?Possible Bug?)
0.5 Initiative per Point
0.5 Start Action Points per point
1% Critical Chance per point
Unknown increase to chance to detect traps and hidden objects. More then likely these have a pre-set perception score requirement and a check is made to see if you have enough.
5% Ranged Penalty Reduction per point
Derived Statistics
Initiative = 0 + (Speed/2) + (Perception/2)
Movement = 1 + (Speed/10)
Defense Rating = 8 + ((Dexterity - 5) x 2)) (Minimum 0)
Start Action Points = 2 + (Perception/2) + (Speed/2)
Turn Action Points = 4 + ((Speed - 1) / 2)
Maximum Action Points = 7 + Constitution
Critical Chance = Perception - 5 (Minimum 0)
Ranged Accuracy
Having spent some time testing this to work out the "Math" involved in the calculation, I thought this deserved its own section as the explanation is rather complicated.

Maximum Range = Your weapons max range, for instance crossbows are 22
Range = The Range in meters of your target
Base Penalty Percent (BPP)= Range / Maximum Range example 15/22 = 0.68
Penatly Reduction (PR) = 5% per point of Perception example 10 Perception = 50%
Ranged Penalty Percent (RPP) = Base Penalty Percent * Penatly Reduction example 0.68 * 0.5 = 0.34
Hit Percent = (Offence Rating - Targets Defence Rating) * (1 - Ranged Penalty Percent) example (70 - 15) * (1 - 0.34) = 36.3 Percent chance to hit.
Conclusion that can arrived at from the above information? If you want to be incredibly accurate at long range, you need to get your Perception up as close to 20 as you can, but, you also need to get your Dexterity fairly high as well, since perception only reduces the penatly, but doesn't actually increase your chance to hit. TLDR: At 20 Perception all ranged attack penalties are gone.