A character consists of skill points (allows you to choose skills = specialization for accessing abilities. Example: "one-handed weapons"), abilities (e.g., dual wielding in the one-handed weapon branch), and attributes (strength, etc.).
Attributes provide parameters (health, evasion, accuracy, immunity, etc.).
Parameters work differently in combat, but most often in the form of checks. Let's say someone attacks something with a sword. "Someone" has 50 accuracy. "Something" has 100 evasion. The game rolls a check of 1-50 accuracy against 1-100 evasion. If the check succeeds, there is a hit.
Damage is the base damage of the weapon, plus modifiers (e.g., from strength), but the result is reduced by a percentage if the defender has armor.
The battle itself takes place on a grid. The base speed was 3. I don't know what it is now.
There can also be various checks outside of combat. For example, immunity to poison.
That's roughly it...
If it's not clear how to play in principle, you create a character and then write down their actions. The result of the actions is determined by the game master by default.