Setting up multiple monitors displaying different screens on a Chromebook 14

Hi, I'm curious how to run three external monitors all displaying different screens on my Acer Chromebook 14. I bought an HDMI splitter and am running my laptop via the splitter to three external monitors, but it only allows me two different displays (my laptop screen can display one thing, but my three external monitors can only mirror each other rather than allowing a different display on each screen). When I go into Settings > Device > Displays, it only seems to recognize one monitor as being connected event tho via splitter there are three monitors connected. Any help in fixing this appreciated - thank you!!