Stabilitrak, parking brake, and ABS lights are on
 

I went to start my 08 chevy equinox yesterday and nothing would happen. The lights would flash for a second but the truck would not start. I called onstar and they sent someone out to try to give me jump but he didn't know what he was doing so I told him he could leave. I asked a family friend for help and they came over and tried to give me a jump and still nothing. After a while the truck lost all power to where I couldn't even get the keys out of the ignition. So we ran to Walmart and purchased a new battery. As soon as we took the old battery and set the new battery in and laid the positive and negative wires on it, the truck started to get power back. We reconnected the negative and positive wires to the battery and the truck started right up. As soon as we started to drive out of the garage, the stabilitrak, parking brake, and ABS lights all came on and the truck dings for about 30 seconds. I researched this on the internet and found where one customer unconnected the negative wire from the battery and let it sit for about 5 minutes and after reconnecting it, all lights went away. So I tried that and when I started the truck again, all the lights are still on. I don't know what else to do. I know that there is nothing wrong because none of those lights were on before I changed the battery. I can not afford to take the truck to the dealership because they charge $100 just to look at it. Please help me.

If by "parking brake" light you mean the red BRAKE! light, make sure the parking brake is fully disengaged and check the fluid level in the brake master cylinder. Aside from the warning light self-test when your first turn the key to the RUN position, those are the only two reasons why the red brake light would be lit up.

Well truthfully you should unplug both battery terminals and try that, but I doubt it will change anything

You could possibly have a bad abs sensor

The stabilitrac light comes on, as do others if the vehicle isn't generating enough battery voltage. If you have a volt meter, the voltage at the battery with the engine running, should be at lease 14.2 volts. If not, you have a charging system issue that's likely causing your issue.