When I read a slide on a tab do I pick or just slide or both?



Talking specifically for solos.
pick the string with your finger on fret 12, then with the string still vibrating, slide up to fret 15
pick the note, if the first number is in (x) than you don't have to pick.
You only pick the first note, then slide to the second one. That's why it's a slide - otherwise it'd just be two successive notes.