How to include run a program on devc++ when i have my own .h file..i have my own headerfile, but when i run my main.cpp it says, no such file or directory

www.codeproject.com/KB/recipes/csha1/CSHA1-2.1-Source.zip i downloaded d sha1(a hash algo) code from d given link,but i don't know how to use this zip file to encrypt my msg. pls help!