如何在本地驱动器中安装python3？

如何解决如何在本地驱动器中安装python3？

我正在尝试在Windows 10上安装PX4固件，并使用Cygwin工具链构建了它。但是，当我使用make命令构建程序时，它显示python3不可用。我已经安装了Python 3.8，它在Git bash中显示，为什么它在控制台bash中不显示？

错误：-

-- Could NOT find PythonInterp: Found unsuitable version "2.7.14",but required is at least "3" (found /usr/bin/python)
CMake Error at CMakeLists.txt:287 (message):
  Python 3 not found.  Please install Python 3:

      Ubuntu: sudo apt install python3 python3-dev python3-pip
      macOS: brew install python


-- Configuring incomplete,errors occurred!
See also "/cygdrive/c/PX4/home/Firmware/build/px4_sitl_default/CMakeFiles/CMakeOutput.log".
Error: /cygdrive/c/PX4/home/Firmware/build/px4_sitl_default is not a directory
make: *** [Makefile:226: px4_sitl] Error 1

注意：环境变量中显示python3.8的路径正确