Young kid with a lot of questions.
 

So, I live near Tampa FL and own a 2019 SS and me plus a couple of friends installed some Long Tube Headers from Speed Engineering on it and we are waiting for my axle back to come in from AWE so at the moment the piping sits right past the rear axle. These have no CATS and the axle back doesn't come with mufflers. I wanted straight, unapologetic aggression which I already understand not everyone likes so please hold your opinions. I'm young and dumb so let me be lmao.

I have a C.E.L for what I presume is not having the rear O2 sensors plugged in.
My question is what should I do now?
Do I have to tune the C.E.L out? And if so, would I need a personal hand held tuner? Would it be better/cheaper to take it to an actual tuner?
Someone suggested "dummy plugs" which I don't know if those are even a real thing but figured I'd ask.

Plus the axle back I bought from AWE is only a dual tip exhaust and not quad tips so I was wondering if I could take it to a shop and have them weld something to turn it into a quad tip axle back?

I know a lot of you experienced guys/gals are gonna have a good laugh probably but hopefully someone could just give me guidance on what to do. I don't want to mess anything up and want this done properly.

Thank you in advance!

You need to have it tuned and the tuner can remove the rear o2 sensors from the program.

Yea you need a tune since you got headers. Shouldn't be driving around a lot without a tune or at least not going WOT. A tune will take care of all the check engine lights.

Yea a shop should be able to weld on some quad tips pretty easily.