First and foremost

Your pure JavaScript skills are themost important. Even after choosing a framework, because if you want to get a job in the industry now you have to choose one, you should always keep working on your pure JavaScript skills. Ain't no framework scary, when your core JavaScript skills are on point.

Disclaimer: This article is only my opinion.

That said,

I am going to recommend you the only framework I know -React. This is my favourite one, I tried once Angular and didn't understand it at all, so I went back to React. This awesome framework is actually a library with great and awesome open-source tooling around it, which makes it a framework.

What's React ?

Exact definition you can find atreactjs.org, I am gonna write I few points, why I think React is the best framework for beginners.

React:

•  Is dominating the job offer postings now in the Frontend Development world, it's popularity is still rising and knowing it well can get you a job quick.
•  Has very little framework-specific methods, you actually write mostly pure JavaScript when working with it.
•  Has the best and awesome tooling around the framework, you can find library for just anything, which makes it easier development.
• Has a very pleasant, declarative way of writing small code building blocks, whom which you'll build bigger blocks, which makes an easy way of building applications
• You can create Native Mobile applications with it - React Native is the biggest cross-platform framework for creating mobile apps.
• You can also create Desktop applications with it. Electron make's it possible for you.
• There's a massive amount of free knowledge on React online!

And many more...

Summary

You learn React once and you can use this knowledge and way of working for all the platforms you like - Web, Mobile, Desktop. As a beginner this is awesome thing, because you want to learn enough to get a job first and then you can go with it wherever you want.

This makes you a very flexible developer. I've been working with React for more than a year and almost a year with React Native now. I love it and I don't plan to move from it.

Have a nice day!