I got my 2000 3.8 v6 mustang convertible last week and I drove her to work she was working just fine on the test drive and got me to work good but when I went on my lunch break to drive her she wouldn’t start I changed the battery cuz it was cold and the cca was low I get power to the inside of the vehicle but she wont crank click or do anything I even got a jump and nothing happened was wondering what could be the issues cuz she’s stuck at work and won’t move can’t even put her in neutral...

Won’t start need some help