Help with Front-End application development

Hey everyone! This is my first time posting in this subreddit. I want to start applying to internships for this summer, and have begun working on some personal projects. However, much of my expertise come back-end engineering as a result of college classes, and know very little about front end development. For example, one project I want to work on is a path-finding visualizer. I was wondering if anyone could give me a few pointers on how to get started on front end development, as well as what tools to use? Any help will be appreciated!