Hi,
Welcome to our community! 
Are there any error messages in your console?
If not, try to replace Vector2.MoveTowards with Vector3.MoveTowards in the EnemyPathing class.
If the enemy moves but keeps appearing at an unexpected position, check which WaveConfig file gets used in your game. Just because you created multiple WaveConfig objects does not mean that they get used automatically.
If the enemy does not move at all, please rewatch the video at least one more time. Also compare your code to the Lecture Project Changes which can be found in the Resources of this lecture. Maybe a detail is missing either in your scene or in your code.
See also:
- Forum User Guides : How to mark a topic as solved