Degrees of obscurement
Just like cover, obscurement is directional, you may have it vs some creatures and none from others. If so, you are hidden from one, and not hidden from another. See the Point Out Action
Lightly Obscured
Tall grass, bush, light fog
Heavily Obscured
Pitch darkness, thick jungle, heavy fog. If you benefit from standard cover, you are considered heavily obscured
Completely Obscured
No way to see, completely covered, thick wall. If you benefit from heavy cover, you are considered completely obscured
Hide
1 Action
You can attempt to hide from an enemy provided you are obscured from. When you do so, you make a stealth check against the target’s passive perception DC. This stealth check is also used against any seek action
You are considered hidden until you are discovered. This can happen either with the seek action or
Seek
1 Action
You can attempt a seek check to locate a creature hidden from you. Make a perception check vs the creature’s stealth roll. On an equal or higher level, the creature is no longer hidden from you.
Point Out
Interaction
A creature can point out a creature who is hidden from another creature. When done, the creature's stealth check is reduced by 5
Attacking From Stealth
When you make an attack when attacking when hidden, the target is considered off-guard. However if you move more than 10ft before attacking, you must make another stealth check. If the target is in melee, or doing something(such as holding an action against someone other than you), you gain advantage in the stealth check.
Group Stealth Check
If the party is making a group stealth check, the GM takes the average rolls of everyone stealth checks.
Stealth Check over time
Characters must make repeat stealth check at the GM’s discretion based on the situation. Usually this should be when entering a new area, or when new variables are added.