Hi @Zizima,
Welcome to our community! 
NullReferenceException means that a reference (“link”) to an instance is missing. Double click on the error message to see to which line in your code it is referring. If you exposed a field in the Inspector, make sure that it’s not empty.
Those messages with the yellow icons are harmless warnings, probably caused by a bug in Unity. Double click on each message in your Console, and add = default; behind the respective variable declaration.
Did this help you fix the issue(s)?
See also:
- Forum User Guides : How to mark a topic as solved