A skill check tests a character’s innate talent and training to overcome a challenge.
The Game Master sets a Difficulty Class (DC) as the threshold that the character must meet to accomplish what they’re trying to do. The player then rolls a d20, adding their Attribute modifier and any relevant bonuses or penalties.
If the sum is equal to or higher than the DC, the creature succeeds. If not, it might fail or succeed partially, depending on the GM.
Your Skill Check = d20 + your relevant Attribute (+ proficiency bonuses if applicable) (+ bonuses/penalties from Conditions or Perks)