I illustrator for designing and that’s what I’ve used for web design (but only because I haven’t learned any UX design software yet ) Once you get the hang of it, it’s incredibly easy, flexible and fast to work with, because it’s vector based/focused, which photoshop isn’t (I only really ever use photoshop for photos).
Adobe XD is now for free, so that will be my next software to learn. I see it as somewhere to start before moving on to something more suitable, ie Sketch.
I use 80% Lynda and 20% youtube when learning new software. Lynda is invaluable to me, their videos have helped me get up and running in new software in a matter of hours!