What is it? I need to configure some things through Terminal and it won't use the ./configure command...what is the Mac configure command?

It's conventional that projects which are built from the command line are configured with a script named 'configure' before you start building them. The configure script is part of the project, not something which would be installed on your system in the first place.

To use the script, all you have to do is find it in the project distribution, cd to its folder, then type './configure' to execute it.