Depends on what bootloader is installed if one exists and you want to do serial downloads.
If no bootloader exists and the chips is a 328P running at 16 MHz, I'd install Uno bootloader. Or select Uno as the board type, connect an AVR programmer to its ISP/ICSP header, and use File:Upload Using Programmer to load a sketch and not have a bootloader.
Provide a link to "RedBot" for a more definitive answer.