If I teleported here from the 90s, first thing I'd need to wrap my head around is how HTML and CSS have changed. I'd be learning a responsive framework (or even hand-rolling it, so you know how it works) like bootstrap. And doing a very basic website.
And if html5 & responsive css aren't enough to wrap your head around at once, I'd create a github account, and start with github pages. That'll let you use the static site generator Jekyll. The combination of all three will do pretty much all you need for 90% of the sites out there.
After that, then I'd look at a stack that lets you have some degree of interactivity and persistence in order to build web apps.... But for now, clean responsive websites would be the way forward.
Also for static site generators take a look at:
When you need to go beyond static sites and take a look at the web frameworks - Ruby on Rails is the obvious one, but I reckon that Meteor (https://www.meteor.com/) could be a good bet now that it has matured. Might save you a lot of time when compared to RoR for certain tasks.