Starting with FPGA boards

I think you can find floating point ip (maybe free?) as for a UART, this is relatively easy to implement, search this forum for uart. You can instantiate multiple of these entities, but that does not take care of signal levels etc. So maybe you can find all the components you need and you only need to create the glue logic to put it all together. This is a bit like making a pcb; you get all the ic's and then you solder them together. But the question you might want to ask is why use an FPGA. You have ip to read from a camera, but more image processing examples are available on computer (I think).