Hey Jade,
Pretty much any PADI OW scuba instructor is qualified to teach a rescue course. I don’t know the other agencies’ requirements.
I find the best courses are when you have several students and a few divemasters and assistant instructors. That way the instructor can add an element of chaos and make it more real. If you want to get a group together, let me know when.
You don’t need any special gear. You’ll need books and you’ll want to watch the video. You will need a CPR/First aid certification but your instructor ought to be able to give you that training if you need it.