poll.h and unistd.h is for Unix-like systems and not available on Windows. If you are using VS2019 on windows, you can modify utlis.h:
change #include<poll.h> into #include<winsock2.h>
change #include<unistd.h> into #include<io.h>

change poll into WSAPoll
Since WSAPoll's binary lib is in ws2_32.lib, you'll have to add:
#pragma comment(lib, "ws2_32.lib")
to utlis.h file
my ws2_32.lib is located in "C:\Program Files (x86)\Windows Kits\10\Lib\10.0.19041.0\um\x64\WS2_32.Lib" (I'm using x64, select your own architecture)