A great starting point for your journey into web development is getting familiar with Angular2, particularly using Typescript as the language of choice.
Angular2 was built from scratch with Typescript, making it a powerful and efficient framework.
Once you dive in, you'll discover the abundance of features that Angular2 offers, including simplified component testing.
You have the option to work with javascript, dart & typescript in Angular2, but many find that Typescript is preferable due to its ease and benefits. It involves a conversion process from typescript to javascript.
If you're transitioning from Angular1.x(with JS), be prepared for some differences as Angular2.0 is quite distinct. However, considering that Angular1.x will eventually phase out in favor of Angular2.0, it's wise to start learning now.
Furthermore, there are resources available for migrating your existing Angular1.x projects to Angular2.0 through the upgrade process.
There's so much more to explore, but hopefully this information sets you on the right path.