Infocus LP640 Projector with Apple TV/MacBook

I have a (very outdated) Infocus LP640 projector that I want to hook up to my Apple TV (tvOS 13.4.8) and MacBook. Which adapter should I buy and which ends female/male do I need? I have read so many different suggestions for HDMI, DVI, VGA cords...and none of it makes sense to me, haha! Also, is it possible to hook up both Apple TV and MacBook with a single USB adapter, or should I purchase 2 adapters?

I would also like to use a better sound source because the audio currently comes out of the projector's not-so-good speakers. Is this possible? The projector has a headphone jack, so could I just use an aux cord to any speaker?

I found a similar post from years ago with the Infocus LP540 projector to help: https://discussions.apple.com/thread/3920541.

Here is a link for a manual of the projector: https://www.manualslib.com/manual/282453/Infocus-Lp650.html?page=2#manual.

Thank you!