How do I check if a game object exist in hierarchy ?

i want to check if a prefab exist in hierarchy and when it not exist i want to move on to the next level, i want to check if a prefab existing in hierarchy and when it not exist i want to move on to next level

@sa3ido
1. Use tags for the prefab.
2. If GameObject go = GameObject.FindGameObjectWithTag(“your_tag”) returns a null, it doesn’t exist in the hierarchy.
3. in that case move on to the next level.