What is a framework that should a developer kick start as a Front End developer

Other than calling a javascript framework a framework, an eligible professional front-end developer when building front-end apps should at least be able to build apps with that framework, and a front-end framework has a set of theories.

For example, if someone wants to find a job that requires the skill in a certain framework, the common components that should be done should include a menu, tree, layout, etc These basic components which people call a framework most often. And very often, the dashboard has some charts for statistics.

Many years ago I build a sole frontend app as Cloud platform, I built all the pages and all charts, nowadays things have become easier than before since there are these MVVM frameworks which makes development easier.