The chip handles all USB protocol internally. Your computer sees it as a virtual COM port (VCP) or a D2XX device. But the "utility software" people search for usually falls into three categories.
After downloading CDM v2.12.28 WHQL Certified.zip , run the executable. It automatically detects an FT245RL in either VCP or D2XX mode. Most stability issues with "FT245RL utility software download" stem from mismatched driver versions—always grab the latest CDM package.