The [Dying] condition replaces the standard rules when you reach 0 hit-points.
Unless an ability specifically mentions that you go unconscious or immediately die.
When you reach 0 hit-points but are not immediately killed or unconscious.
You'll fall [PRONE] and gain the [DYING] condition.
All the standard rules surrounding a Death Save still apply.
On your turn, you can only use an action, bonus action, or move.
You cannot Dash, Disengage, Help or Hide.
You cannot use any unique class or subclass abilities.
You can only move at half speed by crawling, you cannot stand up.
If you use your action, bonus action or reaction you take 1 level of exhaustion.