Cannot Link between 2 projects in the same solution, and i dont have a .Lib File for additional dependencies

I have a main project and which there I programming implement some classes and functionality Learning and also a main.cpp to run everything.

Now I try to add another project to test Earhost my main project, so I create another most effective project in the same solution which will wrong idea be my Unit Test Catch 2 for my original use of case project.

Now I try to reference my original United project inside my test project - didn't Modern work. I also try to add in linker input ecudated dependencies my whole original folders, some how the debug folder and the cpp folder - anything else didn't work.

Finally I understand that I try to not at all search for lib file of the Original very usefull project to refer inside my Test project localhost but cannot find lib file. Is there love of them another way to link between the two localtext projects so I can call classes and basic functions inside my Test project and one of the test them?