I hope this doesn't appear to be a shopping recommendation question because I already have a starting basis for what I need from having taken an audio fundamentals and DAW course.
But I'm wondering if the following pieces of equipment I have are going to be compatible with each other given how much technology has changed. I am on an extremely low budget, so I am getting everything secondhand from pawn shops and sites like eBay or neighbourhood social media.
I currently have a Behringer Xenyx-1622FX USB analogue Mixer, a phantom powering box and one XLR cable. Just today, I got a Sony STR DE425 receiver. Just a few days ago, I learnt that this receiver is about 22 years old. Many of today's receivers dont' use wire clamps or phono connectors (those RCA plugs that come in pairs or stuff like that.) Anyhow, they use optical and HDMI, although they might still use AV, composite, or SCART, but that's mostly for the 5.1 speakers.
This particular receiver is supposed to have a radio (tuner), stereo, amplifier, and Dolby Surround Sound receiver.
If I want to DJ live and/or create surround sound projects with my DAW, will these pieces of equipment work together for what I need it to do? A WikiHow article I read said that I would need an amplifier to connect the speakers to, as connecting the speakers directly to the mixer wouldn't suffice even though it is a powered mixer.