Looks like part of a package. Unity has adopted an infuriating habit of barfing useless packages into new projects, saving nobody any time since anyone who needs such a package would know how to install it in mere seconds. And yet it continues to trip up new users every single day.
This looks like the test framework package, so try and remove it from the PackageManager, available at Window → Package Manager.
Generally speaking if you see a package in there you don’t need, remove it.
And just from a more general standpoint, for “real” errors that you actually make yourself (I don’t think the above is your fault!), here is my standard blurb:
Remember: NOBODY memorizes error codes. The error code is absolutely the least useful part of the error. It serves no purpose at all. Forget the error code. Put it out of your mind.
The important parts of an error message are:
- the description of the error itself (google this; you are NEVER the first one!)
- the file it occurred in (critical!)
- the line number and character position (the two numbers in parentheses)
All of that information is in the actual error message and you must pay attention to it. Learn how to identify it instantly so you don’t have to stop your progress and fiddle around with the forum.
How to understand compiler and other errors and even fix them yourself: