none of these answers are wrong, per se, but OP might been in need of some more detailed help...
if you're sending different images to the two projectors, either completely separate images or as two halves of a single blended
image, you'll need two physical outputs from the computer. some computers can do this directly, other need specialized hardware. for example any
mac that uses the m1 pro, m1 max, m1 ultra, m2 pro, or m2 max
processor can support two or more screens via usb-c-to-hdmi or usb-c-to-displayport adapters. if you have one of these macs, you could buy two (relatively) inexpensive usb-c-to-hdmi adapters, and then you'd have 2x
hdmi outputs.
to extend
hdmi over long distances, you have several options. the simplest (and probably cheapest) is to use hdbaset which is a technology that uses a single cat5e or cat6 cable to carry
hdmi video. here's a link to a monoprice kit for $130
This Blackbird™ 4K Pro HDBaseT™ Extender Kit allows you to extend High Speed HDMI® signals using a single Cat6 Ethernet cable. It supports extension of 4K@60Hz video to distances up to
www.monoprice.com
hdmi goes into the first box, then CAT6 goes from the first box to the second, up to 70 meters away, then
hdmi comes out of the second box.
you'll need one set of boxes for each
projector.
if your computer does NOT easily support multiple displays, you'll need to tell us what kind of computer you're using and what software you're using so that we can recommend a compatible device to add video outputs.
