How do I fix a linker error in Clion when there seems to be no problem with the code?

So, I have no code, just empty files and a CMake, but I keep getting that Linker Error. Can someone please explain in a lot of detail what my problem is? Some info I have is that I am supposed to be using Visual Studio 2015 as my compiler and stuff, which I think I already have set up.

The Error:

[100%] Linking CXX executable Debug\CinderGame\CinderGame.exe
NMAKE : fatal error U1077: '"C:\Program Files\JetBrains\CLion 2020.2.3\bin\cmake\win\bin\cmake.exe"' : return code '0xffffffff'
Stop.
NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\nmake.exe"' : return code '0x2'
Stop.
NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\nmake.exe"' : return code '0x2'
Stop.
NMAKE : fatal error U1077: '"C:\Program Files (x86)\Microsoft Visual Studio 14.0\VC\BIN\nmake.exe"' : return code '0x2'
Stop.
LINK Pass 1: command "C:\PROGRA~2\MICROS~1.0\VC\bin\link.exe /nologo @CMakeFiles\CinderGame.dir\objects1.rsp /out:Debug\CinderGame\CinderGame.exe /implib:CinderGame.lib /pdb:C:\Users\cesar\Documents\GitHub\final-project-cesarmonsalud\cmake-build-debug\Debug\CinderGame\CinderGame.pdb /version:0.0 /machine:X86 /debug /INCREMENTAL /subsystem:windows /NODEFAULTLIB:LIBCMT /NODEFAULTLIB:LIBCPMT -LIBPATH:C:\Users\cesar\Desktop\cinder_0.9.2_vc2015\lib\msw\x86 C:\Users\cesar\Desktop\cinder_0.9.2_vc2015\lib\msw\x86\Debug\v140\cinder.lib kernel32.lib user32.lib gdi32.lib winspool.lib shell32.lib ole32.lib oleaut32.lib uuid.lib comdlg32.lib advapi32.lib /MANIFEST /MANIFESTFILE:CMakeFiles\CinderGame.dir/intermediate.manifest CMakeFiles\CinderGame.dir/manifest.res" failed (exit code 1120) with the following output:
LIBCMTD.lib(exe_winmain.obj) : error LNK2019: unresolved external symbol _WinMain@16 referenced in function "int __cdecl invoke_main(void)" (?invoke_main@@YAHXZ)
Debug\CinderGame\CinderGame.exe : fatal error LNK1120: 1 unresolved externals

The Code:

cmake_minimum_required(VERSION 3.12 FATAL_ERROR)
set(CMAKE_CXX_STANDARD 11)
project(Connect4)

# This tells the compiler to not aggressively optimize and
# to include debugging information so that the debugger
# can properly read what's going on.
set(CMAKE_BUILD_TYPE Debug)

# Let's ensure -std=c++xx instead of -std=g++xx
set(CMAKE_CXX_EXTENSIONS OFF)

# Let's nicely support folders in IDE's
set_property(GLOBAL PROPERTY USE_FOLDERS ON)

# Warning flags
if(MSVC)
    # warning level 3 and all warnings as errors
    add_compile_options(/W3)
else()
    # lots of warnings and all warnings as errors
    add_compile_options(-Wall -Wpedantic -Werror)
endif()

# FetchContent added in CMake 3.11, downloads during the configure step
include(FetchContent)

# FetchContent_MakeAvailable was not added until CMake 3.14
if(${CMAKE_VERSION} VERSION_LESS 3.14)
    include(cmake/add_FetchContent_MakeAvailable.cmake)
endif()

FetchContent_Declare(
        catch2
        GIT_REPOSITORY https://github.com/catchorg/Catch2.git
        GIT_TAG devel

)

# Adds Catch2 testing library
FetchContent_GetProperties(catch2)
if(NOT catch2_POPULATED)
    FetchContent_Populate(catch2)
    add_library(catch2 INTERFACE )
    target_include_directories(catch2 INTERFACE ${catch2_SOURCE_DIR}/single_include)
endif()

get_filename_component(CINDER_PATH "C:/Users/cesar/Desktop/cinder_0.9.2_vc2015" ABSOLUTE)
get_filename_component(APP_PATH "${CMAKE_CURRENT_SOURCE_DIR}/" ABSOLUTE)

include("${CINDER_PATH}/proj/cmake/modules/cinderMakeApp.cmake")

list(APPEND CORE_SOURCE_FILES
        )

list(APPEND SOURCE_FILES    ${CORE_SOURCE_FILES}
        include/core/Connect4.h
        include/visualizer/FinalProjectApp.h
        src/core/Connect4.cpp
        src/visualizer/FinalProjectApp.cpp
        )

list(APPEND TEST_FILES tests/Connect4Tests.cpp)

ci_make_app(
        APP_NAME        CinderGame
        CINDER_PATH     ${CINDER_PATH}
        SOURCES         apps/cinder_game.cpp ${SOURCE_FILES}
        INCLUDES        include
)

ci_make_app(
        APP_NAME        ConsoleGame
        CINDER_PATH     ${CINDER_PATH}
        SOURCES         apps/main_console_game.cpp ${SOURCE_FILES}
        INCLUDES        include
)

ci_make_app(
        APP_NAME        GameTest
        CINDER_PATH     ${CINDER_PATH}
        SOURCES         tests/Connect4Tests.cpp ${SOURCE_FILES} ${TEST_FILES}
        INCLUDES        include
        LIBRARIES       catch2
)


if(MSVC)
    set_property(TARGET GameTest APPEND_STRING PROPERTY LINK_FLAGS " /SUBSYSTEM:CONSOLE")
endif()