❔ WPF app unit testing

I am learning how to make unit tests. I built my app on .net core 6.0 and I created class library (on .net core 6.0 too), when I add dependencies I have that error on picture. I am watching that tutorial: https://www.youtube.com/watch?v=ub3P8c87cwk, but he uses .net framework. Thank you in advance for help.

IAmTimCorey

YouTube

Intro to Unit Testing in C# using XUnit

Unit testing is an important part of writing quality software. It is also a controversial and somewhat difficult topic to get started in. In this video, we walk through why we would use unit testing, what a unit test is, how to create a test, and how to deal with some of the more difficult situations. Along the way, we will cover best practices...