Compiling errors on github projects without .sln files

I’ve downloaded two separate C++ sample projects to see how they work.

When I try to open the project, Unreal attempts to compile it. It shows a log while it’s running, and I try to watch but as soon as the compilation process fails, the log window is closed and all I get to see is a ‘Things failed, try to continue or give up?’ dialog.

This doesn’t give me any help. So I figured I’d open the projects in Visual Studio to see its compiler output. Both apparently have .sln files ignored in their .gitignore. Where do I go from here, how should I manually set up a .sln file for a project I’m unfamiliar with?