Need help wiring a LED brake light bar on my 2021 Mk7.5 S N.A version

[GyeTI1702]

I have a LED brake light bar with different functions (turn signal, backup, etc) and cannot seem to find anything like a wiring diagram for the oem LED mk7.5 taillight other than conversion harness DIY. If anybody knows what the cable colors function are on the outer plug i found and if those would work or any idea where to wire? (ACC, GND, etc) None of the plugs I've seen online look or have only 4 wires like mine does and im honestly not knowledgeable since I've only ever had an older car with simple white red and black wiring for lights. If this isn't the correct place to post this my apologies i just joined

 

[where2]

Welcome, Great first question!

Your first problem is that a Mk7.5 uses PWM (pulse width modulation) for driving the existing LED rear lights at varying levels of brightness. If you really want to install this rear light bar, I'd suggest installing a Tekonsha GTI Mk7.5 trailer light adapter kit, and run dedicated power to the fuse panel, then plug your Brake Light Bar into the flat four trailer plug with ground, tail, right turn/brake, and left turn/brake wires (like a typical trailer). The Tekonsha kit is a plug-n-play kit that accepts the stock wiring from the car, and plugs into the existing tail lights. It senses everything it needs to know from being a "man in the middle", and drives dedicated transistorized "relays" to feed the output leads for trailer lights, using the power lead you ran from the fuse panel. This setup doesn't draw any power from the stock rear light wiring, or interfere with the tail lights.. It merely senses the PWM signal and switches a transistorized relay to generate a "switched" 12v like cars used to have at the tail lights years ago. Best of all, it doesn't throw any codes.

I'm in Palm Beach, where's your project car? (I actually have a Tekonsha GTI kit in my 2019 e-Golf).
Do you have a link to an instruction set for the light bar?