Can I use my 5K iMac as a monitor for the Mac Pro?

I am so curious because I really need fast speed for Final Cut, but for the Mac Pro, you need to buy things separately (monitors, keyboards, mouses). For the iMac, it is included, but like it really ***** that the Mac Pro has that old Thunderbolt which is very pixelated at 82ppi, as compared to the cheap iMac 21.5" without Retina Display, it equals 102ppi. My 27" iMac is 5K too, and the iMac is 218ppi. I want a high resolution to get the best view possible, but I cannot within the Mac Pro. I also want the monitor to have a built in webcam, and even speakers.