Ninja Error

[HarpreetHeera]

mkfatfs_Jkearins is Project folder.

C:\esp-idf\examples\mkfatfs_Jkearins>idf.py set-target esp32

C:\esp-idf\examples\mkfatfs_Jkearins>idf.py build
esptool.py v2.9-dev
Generated C:/esp-idf/examples/mkfatfs_Jkearins/build/bootloader/bootloader.bin
[905/906] Linking CXX executable mkfatfs_Jkearins.elf
FAILED: mkfatfs_Jkearins.elf
cmd.exe /C "cd . && C:\Users\Administrator.espressif\tools\xtensa-esp32-elf\esp-2020r2-8.2.0\xtensa-esp32-elf\bin\xtensa-esp32-elf-g++.exe -mlongcalls -Wno-frame-address @CMakeFiles\mkfatfs_Jkearins.elf.rsp -o mkfatfs_Jkearins.elf && cd ."
c:/users/administrator/.espressif/tools/xtensa-esp32-elf/esp-2020r2-8.2.0/xtensa-esp32-elf/bin/../lib/gcc/xtensa-esp32-elf/8.2.0/../../../../xtensa-esp32-elf/bin/ld.exe: esp-idf/esp32/libesp32.a(cpu_start.c.obj):(.literal.main_task+0x18): undefined reference to app_main' c:/users/administrator/.espressif/tools/xtensa-esp32-elf/esp-2020r2-8.2.0/xtensa-esp32-elf/bin/../lib/gcc/xtensa-esp32-elf/8.2.0/../../../../xtensa-esp32-elf/bin/ld.exe: esp-idf/esp32/libesp32.a(cpu_start.c.obj): in function main_task':
C:/esp-idf/components/esp32/cpu_start.c:551: undefined reference to `app_main'
collect2.exe: error: ld returned 1 exit status
ninja: build stopped: subcommand failed.
ninja failed with exit code 1

C:\esp-idf\examples\mkfatfs_Jkearins>idf.py makefatfs
Executing action: makefatfs
ninja: error: unknown target 'makefatfs'
command "makefatfs" is not known to idf.py and is not a Ninja target

Thanks.