Ckncerning the RAM, as you will generate the hardware, yes you are a developer. The ammou t of RAM needed depends on your design and target chip. You can try with 4GB, but it miht not be enough, I work with an Arria 10, which needs 64 GB, that is the only rference I got.
You don't write C, you write OpenCL, which is C with some added functionality, and some "removed" functionality.
In the case of not having a board, I think you can use the emulator. Please see this thread:
http://www.alteraforum.com/forum/showthread.php?t=51433. I also think you don't need much RAM for that, but I haven't checked that.