99 chev 1500, u turn the key , and nothing happens.. radio lights everything comes on. So I get down and cross the 2 wires on starter, and it fires but don't crank. I get back up check fuses with light tester everything looks good. I try one more time turning over and it tries to start but nothing I try again and again , but seems battery is dying but battery is 3 months old. I try again and nothing , radio everything on but nothing no click click from starter

Remove and fully charge the battery. Most auto parts stores will do this for free. Afterwards, this link should help:

https://www.askmehelpdesk.com/cars-t...tml#post235560

You may also want to have your alternator checked. Most auto parts stores will also test them for free. Otherwise, perform the tests in the link below:

https://www.askmehelpdesk.com/cars-t...ml#post1973613