Can't find package X11 on WSL - cmake

Question

I'm trying to build an opensource project on WSL using cmake.
I'm getting first these two errors which I don't understand :
CMake Error at /usr/share/cmake-3.16/Modules/CMakeDetermineSystem.cmake:185 (configure_file):
configure_file Problem configuring file
Call Stack (most recent call first):
CMakeLists.txt:2 (project)
The CXX compiler identification is GNU 9.3.0
CMake Error at /usr/share/cmake-3.16/Modules/CMakeDetermineCXXCompiler.cmake:210 (configure_file):
configure_file Problem configuring file
Call Stack (most recent call first):
CMakeLists.txt:2 (project)
and for X11:
Searching X11
CMake Error at /usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:146 (message):
Could NOT find X11 (missing: X11_X11_LIB)
Call Stack (most recent call first):
/usr/share/cmake-3.16/Modules/FindPackageHandleStandardArgs.cmake:393 (_FPHSA_FAILURE_MESSAGE)
/usr/share/cmake-3.16/Modules/FindX11.cmake:366 (find_package_handle_standard_args)
CMakeLists.txt:18 (FIND_PACKAGE)
Here is the cmakelist.txt provided :
#CMake for the gard Project
project(GARD)
cmake_minimum_required(VERSION 2.4.0)
#Set the path to the Cmake Modules
SET(CMAKE_MODULE_PATH "${CMAKE_SOURCE_DIR}/cmake_modules/")
MESSAGE("Path to Cmake Modules is " ${CMAKE_MODULE_PATH})
MESSAGE("The source directory of the project is " ${GARD_SOURCE_DIR})
MESSAGE("")
MESSAGE("STEP 1 : SEARCHING FOR NEEDED MODULES")
MESSAGE("")
MESSAGE("Searching X11")
FIND_PACKAGE(X11 REQUIRED)
IF(X11_FOUND)
MESSAGE(" X11 include path: " ${X11_INCLUDE_DIR})
MESSAGE(" X11 library path: " ${X11_LIBRARIES})
ENDIF(X11_FOUND)
MESSAGE("Searching LAPACK AND BLAS")
find_package(LAPACK)
IF(LAPACK_FOUND)
MESSAGE(" LAPACK library path: " ${LAPACK_LIBRARIES})
MESSAGE(" BLAS library path: " ${BLAS_LIBRARIES})
ENDIF(LAPACK_FOUND)
MESSAGE("Searching CIMG")
find_package(CImg)
IF(CIMG_FOUND)
MESSAGE(" CIMG include path: " ${CIMG_INCLUDE_DIR})
ENDIF(CIMG_FOUND)
MESSAGE("Searching pthread")
FIND_LIBRARY(PTHREADS_LIBRARY pthread
PATHS /usr/local/lib /usr/lib /usr/lib/x86_64-linux-gnu
)
IF(PTHREADS_LIBRARY)
MESSAGE(" Pthread library path: " ${PTHREADS_LIBRARY})
ENDIF(PTHREADS_LIBRARY)
MESSAGE("Searching Graphviz")
find_package(GraphViz)
IF(GRAPHVIZ_FOUND)
MESSAGE(" Graphviz library path: " ${GRAPHVIZ_LIBRARIES})
MESSAGE(" Graphviz include path: " ${GRAPHVIZ_INCLUDE_DIRS})
SET(GRAPHVIZ_SUPPORT "#define GRAPHVIZ_SUPPORT")
ENDIF(GRAPHVIZ_FOUND)
CONFIGURE_FILE(GraphVizConfig.h.cmake ${CMAKE_SOURCE_DIR}/include/core/GraphVizConfig.h)
find_package(OpenMP)
if(OPENMP_FOUND)
message("openMP found")
set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${OpenMP_C_FLAGS}")
set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} ${OpenMP_CXX_FLAGS}")
endif()
MESSAGE("Searching FLANN")
find_package(Flann)
IF(FLANN_FOUND)
MESSAGE(" FLANN include path: " ${FLANN_INCLUDE_DIR})
include_directories(${FLANN_INCLUDE_DIR})
SET(FLANN_SUPPORT "#define FLANN_SUPPORT")
ELSE(FLANN_FOUND)
MESSAGE(" FLANN include path not found")
SET(FLANN_SUPPORT "")
ENDIF(FLANN_FOUND)
include(ProcessorCount)
ProcessorCount(N)
if(NOT N EQUAL 0)
set(AVAILABLE_CORES "#define AVAILABLE_CORES ${N}")
else(NOT N EQUAL 0)
set(AVAILABLE_CORES "#define AVAILABLE_CORES 1")
endif()
CONFIGURE_FILE(FlannConfig.h.cmake ${CMAKE_SOURCE_DIR}/include/core/FlannConfig.h)
MESSAGE("")
MESSAGE("")
MESSAGE("STEP 2 : SET INCLUDE AND LIBRARY PATHS")
MESSAGE("")
SET(GARD_INCLUDE_DIR ${GARD_SOURCE_DIR}/include)
IF(LAPACK_FOUND)
SET(LINK_LIBRARIES ${X11_LIBRARIES} ${PTHREADS_LIBRARY} ${LAPACK_LIBRARIES} ${BLAS_LIBRARIES} ${GRAPHVIZ_LIBRARIES})
SET(CIMG_USE_LAPACK "#define cimg_use_lapack")
ELSE()
SET(LINK_LIBRARIES ${X11_LIBRARIES} ${PTHREADS_LIBRARY} ${GRAPHVIZ_LIBRARIES})
ENDIF()
CONFIGURE_FILE(CimgConfig.h.cmake ${CMAKE_SOURCE_DIR}/include/core/CimgConfig.h)
MESSAGE("")
MESSAGE("STEP 3 : Documentation generation")
MESSAGE("")
MESSAGE("Searching DOXYGEN")
INCLUDE(${CMAKE_MODULE_PATH}/FindDoxygen.cmake)
IF(DOXYGEN_FOUND)
MESSAGE("DOXYGEN Dir " ${DOXYGEN_DIR})
MESSAGE("GENERATING DOCUMENTATION")
SET(ENV{GARD_INCLUDE_DIR} "${GARD_SOURCE_DIR}/include")
EXEC_PROGRAM("cd docs;${DOXYGEN_DIR}/doxygen doc.txt"
OUTPUT_VARIABLE MY_OUTPUT
)
ENDIF(DOXYGEN_FOUND)
MESSAGE(STATUS "Link libraries: ${LINK_LIBRARIES}")
MESSAGE("")
MESSAGE("STEP 4 : COMPILATION")
MESSAGE("")
add_subdirectory (${GARD_SOURCE_DIR}/examples)
# add_subdirectory (${GARD_SOURCE_DIR}/operators)
Can you help please? I'm new to cmake and WSL. I'm running WSL on Windows 10 and I've installed the X11 library with " sudo apt-get install libx11-dev " . The command 'cmake .' is running in the bash terminal and looks like :
ananass#DESKTOP-R1E6G2S:/mnt/c/Users/ananass/gard$