So I have a 2000 z28 and I had to jump start it about an hour ago and let it run for about 10-15 minutes and turned it off and it fired right back up but I just went to start it and it’s dead again😑 someone plz help.

 

It could be many things, First thing I would do is get the battery tested. I know it's stating the obvious but people will want a dead battery tested and it doesn't work that way so charge the battery fully before testing because a dead battery will always fail.

 

Computer needs battery power regardless if the vehicle is driven and if it sits long enough it will drain the battery so it's best to leave it on a battery tender. As mentioned start with a healthy battery and it could even be a bad solenoid on the starter so it should also be tested. There could be many things causing your issue but start there and begin checking all of your positive and negative connections..GL

 

I just put a new battery in it about 3 months ago

 

A relatively new battery doesn't necessarily mean that it's still good - they occasionally fail very quickly (unusual but it happens). Do your gauge needles sweep back and forth when you attempt to start the car? That's an almost certain indication of a bad battery.

Of course a recently replaced battery also leads to the possibility that it's a bad connection. Check that the battery connections are clean and tight because grimy or loose connections can cause the same symptoms as a bad battery.