Even if you are only sending in copies digitally, it is a good idea to print your resume (as it’s possible that hiring managers may be doing so) to be sure it prints on a single page, and is easy to read in printed form. Reading over a printed copy of your resume will also help you ensure that there is plenty of white space on the page and it looks professional.
There is not one resume format that works for everyone. There might not even be only one resume format for you and it could benefit you to have multiple formats of your resume available. For example, if you’re applying for a job and you don’t know whether your resume will be submitted through ATS, submit both a chronological resume and use a functional resume for your in person interview.