If you have a serial port, see if you can use it to transfer files to the development board. Generally, xmodem, ymodem, zmodem, kermit and other protocols are used for transmission. You need a software that supports these transport protocols (such as Windows HyperTerminal), and a file system is usually needed on the development board.
If there is a network port, the development board will generally provide servers or clients such as TFTP/FTP. If there is a server on the development board, you can upload files to the development board with the client. Otherwise, you can set up a server and download the files to the development board. Similarly, a file system is usually needed on a development board.
If these conventional tools are not available, you usually need to transplant an operating system (or BSP) to your development board and develop the corresponding communication interface driver software.