Any spells or effects that detect or show undead are triggered by your presence, but Turn Undead doesn't affect you, and you can still be healed by healing spells. You are also immune to Poison and Disease. You do not need to eat or breathe, but you can if you want to. When you take a long rest you do not sleep, instead, if you stay stationary for 6 hours you gain the benefit of a long rest, you are awake and can see during this time.

This replaces the "undead" feature on any compatible race.

Upon death, your body releases an explosion of fertile spores. Every creature in a five foot radius must make a Constitution saving throw, DC 8+con mod+prof. Any creature that fails begins to be infected by the zombie fungus. After 2d10 days the affected creature is completely infected and the fungus is in control. 

This replaces undead fortitude, bone pile and other similar features. If there are multiple you replace one. This feature is optional.