東方紅魔地下 ～ Scarlet Devil Underground
Requires Visual C++ redistributable runtimes: MSVC11 Visual C++ 2012 (x86) and MSVC14 Visual C++ 2017 (x86). You can check under "Programs and Features" or "Add/Remove Programs" whether you have these installed. Otherwise, you will get an error when the program tries to run that "msvcp140.dll" or "vcruntime140.dll". "msvcr110.dll" is actually used by the pre-built OpenAL DLL.
Download the demo here. Also, check out the manual (PDF) before playing.