You must learn to parameterize your path.
can someone show me how to calculate a simple path integral so i can see how they work? more specifically, can it be a problem that involves free particles, preferably a "classic" problem?
I want to understand the concept/idea and be able to perform a simple example, so if you could explain little details a long the way that'd be helpful as well.
here, that might prove useful.
Amazon.com: Quantum Mechanics and Path Integrals (9780070206502): Richard P. Feynman, A. R. Hibbs: Books
And Google is an ideal resource for you to research your question too.
Such research should be attempted before asking other people to do it for you.