Using PIR sensor to activate a video thats being played through projector

I am currently undertaking a project of my own and I have very little to no experience with Arduino. What I want to do is to use a projector in the ceiling which will play a short video when activated, I want the trigger to be a PIR sensor so when someone walks past the video will start playing. I was wondering how I would go about doing this because I have no coding knowledge either? Being new to Arduino I don't really know what I'm doing to be honest

Thanks

Does the device have to switch on both the projector and the video player?

You could probably do this by emulating the IR signals for the devices in question.

Yes I needs to switch the projector on and play the video, this might be a silly question but whats an IR signal, would you have come across any tutorials or anything like that concerning this sort of project?

Thanks

IR is infra-red (a shorter wavelength than that detected by the PIR) used for common remote controls. "Ken Shirriff" "IR" and "Arduino" are useful google search terms.