Help Getting Started

I am hoping to use GraphHopper for a university project but am struggling to figure out where to start as I have little experience with APIs!

I am hoping to use the Routing and Route Optimisation APIs as a base to build off of and make a custom model with my own algorithms and vehicle information. If anyone could help me figure out how to integrate GraphHopper into a new project that would be really useful! I am trying to start my project but don’t know where to start basically