Schools have been trending in this direction for 10+ years, and Chromebooks particularly picked up speed around 2011, five years ago. To stay current as an educator (and employable), I would say every teacher and prospective teacher needs to be knowledgable about iPads and Chromebooks, and have at least cursory knowledge of Macbooks and Windows 7/Windows 10 machines. (The web tools that one can use on Chromebooks can also be used on Mac and Windows machines.) As educators we can't afford for any of these systems to be "foreign" to us. In a hypothetical world where we are all well-prepared, we would all have more knowledge of these systems and web resources than our students do.

The suggestions here are good: read as much as you can, about what you can do and about what pioneering teachers have been doing. You will have to consider this summer as a time to get up to speed so you are ready for fall. Look up Blended Learning, 1:1 computing, Google Classroom, and the whole Google Apps suite of tools. If there is any professional development offered by your district, or nearby, take full advantage of it (public libraries might provide some basic Google Apps classes.) Get to know the teachers in your building who are experienced with technology, get to know them, and see what you can learn from their experience.

A quick Google search for "using Chromebooks in the classroom" turns up dozens of results: start with what you can find there... it looks like there are some nice videos as well as guides that others have written for teachers as advice, as a starting point.