This might be long ill try to keep it short as possible my 99 vette is having issues starting one day I came home from work super and I turned on the inside lights I think are called (courtesy lights) to find my wallet however I was so tired that I left them on for the entire day and it ended up killing my battery and took it to AutoZone to see if they can charge it and they said the battery couldn't hold the charge anymore so I had to buy a new one and it worked the car would crank a little bit but then it would turn on. However, when I try to turn it on the second time it would turn on but still with a little struggle in the beginning but it would say "Pull key, wait 10 sec" so I would turn the car off and then try again the third time where I run I into the issue, the car would crank and crank and barely start giving me on the DIY " reduce engine power" or "low Voltz" when I try to turn the car on" and sometimes the engine will crank and not start at all. As well when I try to just turn the car on not the engine the gauge cluster would not turn on properly just the check engine light and my radio would be the only thing that turn on so this is the issue I'm having rn idk what to do I'm taking the car to the Vette docotos on August 23rd but i wanna know what parts should i get before going like a new ignition switch i already bought a steering column lock bypass but I'm wondering what else should i buy please anyone let me know and sorry that this was long below I'm attach pictures of whats going with he car

 

below is a video of my gauge that appears on the window i forgot what it is called but the numbers are just going crazy so why idk whats going on and why the engine is not turning on

 

I'd let your Vette Doctors diagnose it...why waste your money on parts if you don't have to.

 

Sounds like you have low voltage problems, check all your battery cables including the negative cable where it attaches to the engine block.

 

I didn't ask, but are you proficient with a DVM, it would be easy to troubleshoot if you are.

 

Read the codes via the DIC. This will at least help with the troubleshooting. Since the check engine lite came on and you had reduced power messages there should be some codes set