If you are using Responsive Web Design, use meta name="viewport" tag to tell the browser how to adjust the content. If you use Dynamic Serving, use the Vary HTTP header to signal your changes depending on the user-agent. If you are using separate URLs, signal the relationship between two URLs by tag with rel="canonical" and rel="alternate" elements.
I would focus on building your personal brand online and building a website right away that you can use as a testing ground for learning digital marketing skills. Most digital marketing programs are too theoretical and digital marketing is a fast evolving industries so you need to be constantly learning through active experimentation to become good enough to consistently make money.
Disney/Pixar's Monsters University: Created a Tumblr account, MUGrumblr, saying that the account is maintained by a 'Monstropolis transplant' and 'self-diagnosed coffee addict' who is currently a sophomore at Monsters University.[73] A "student" from Monsters University uploaded memes, animated GIFs, and Instagram-like photos that are related to the sequel movie.

Early versions of search algorithms relied on webmaster-provided information such as the keyword meta tag or index files in engines like ALIWEB. Meta tags provide a guide to each page's content. Using metadata to index pages was found to be less than reliable, however, because the webmaster's choice of keywords in the meta tag could potentially be an inaccurate representation of the site's actual content. Inaccurate, incomplete, and inconsistent data in meta tags could and did cause pages to rank for irrelevant searches.[10][dubious – discuss] Web content providers also manipulated some attributes within the HTML source of a page in an attempt to rank well in search engines.[11] By 1997, search engine designers recognized that webmasters were making efforts to rank well in their search engine, and that some webmasters were even manipulating their rankings in search results by stuffing pages with excessive or irrelevant keywords. Early search engines, such as Altavista and Infoseek, adjusted their algorithms to prevent webmasters from manipulating rankings.[12]