To connect it to your projector, follow these steps.
Connect your computer/device to the projector via HDMI or VGA cable.
Once you've connected the two, turn on your projector and ensure it's set to the correct input source (HDMI/VGA or whatever method you used).
Finally, open the slideshow link on your computer/device you connected to the projector, and it should appear on the projector.
Please note that the exact steps depends on the current setup you have. If the projector is part a venue, I suggest to talk with host/manager to get an assistance.