I want to convert a code from C to C++ , but some statements are very difficult to me , and I have not enough time to make the whole code in C++ from beginning, So anyone who can help me in this regard please comment me then I will comment the code.

It is a snake game code without graphics

Show the C and your C++ code. C++ is C with classes, and some other stuff, like differing syntax for input/output functions. Without code, there is no way to answer your question. FWIW, you can execute your C code if compiled with a C++ compiler, with some minor caveats. The best thing to do to start is to compile the code as C++, and see if it works. If so, then conversion to real C++ will be a minor "inconvenience".