UIpath Community edition and Orchestrator

Can I connect with orchestrator with my Uipath community edition? What are the other prerequisites to take before starting a POC with Uipath community edition?

The easy way of doing this is going to https://lts-platform.uipath.com and creating the tenant.
Then you should follow the instructions on orchestrator training materials to connect it with the robot. It is easy and simple and will definitely be enough for a POC.
Just remember, that after 7 days the tenant will get deleted and you would need to create another one to run the robot.
Hope this helped.