Red light beside key icon stays on

[superskid]

I have a loop of problems and I can't help but think they are all related.

I had some work done at the end of the season last year on my car didn't drive it for months, finally took it out again and it's not working as I remember.

Here is what I notice difference:

- The red light beside the key icon stays on when I drive (pretty sure it didn't)
- Beep pattern seems different when I lock or unlock but I can't tell what is difference (happy to post what it does at specific times if that helps)
- main steering wheel horn doesn't work (Pretty sure it did before work done but maybe not)

Now, all I really had done was a new after market stereo installed. I know there is some metal tab or something that I put electric tape around behind the stereo, but now reading maybe there is a wire or something that something needs to be done too.

When I push the steering wheel horn I can hear a relay or something click, not sure if this is at all related to the stereo, seems replacing the horns or the wiring to them is a common issue but I do hear it click.

So I guess my questions are:

1.) When should the red light beside the key logo be on?
2.) What should the beep patterns be when locking and unlocking with FOB?
3.) What is step 1 for diagnosing horn, I hear relay and fuse is for sure good.

Thanks friends,