I'm using an nRF52832 breakout board to develop a fall detection device. I am using keil to program it. I'm new to this and I want to know if I need a dev board in order to download the code to the breakout board? should it be uploaded via JTAG programmer?
There are probably alternative method for programming, check the docs for your specific part and tools provided by Nordic.
If you want to do programming/debugging within the Keil environment you're going to need a JTAG/SWD pod, and connectivity, to facilitate that.