BBB won't connect to serial

I have a BBB, not very scratched up or anything. I had FreeBSD installed, and that was fun. I decided to get another microSD and an adapter and put Debian on it. I plugged my BBB in to try out Debian, and when I opened Serial (my serial emulator thing), it didn’t show up. Anything i can do to get it to connect? The lights above the plug that you use to connect to computer aren’t flashing. I tried hitting the reset button on my BBB, but it didn’t connect either. What should I do?