We've played around with some designs but most people seem to want the bare PCB - what is the specific use case? If you can get some people interested on the forum, we can spin something pretty quickly for people to try out.
The easiest way is to connect the Particle Photon to the Particle Cloud via your existing WiFi network - yes this is the easiest way to get started. Which Carloop did you order? Did it come with a Particle Photon? If not, you will need to order one.
Yes! You can use Carloop as a webserver and create a tiny HTML page inside the Photon. See Particle's Docs on how to create a SoftAP