Per the article:
Three-pronged Strategy
Xi ordered the regime to focus on three “critical” areas in its pursuit of controlling the global internet.
First, Beijing needs to be able to “set the rules” governing the international system. Second, it should install CCP surrogates in important positions in global internet organizations. Third, the regime should gain control over the infrastructure that underlies the internet, such as root servers, Xi said.
Domain Name System (DNS) root servers are key to internet communications around the world. It directs users to websites they intend to visit. There are more than 1,300 root servers in the world, about 20 of which are located in China while the United States has about 10 times that, according to the website root-servers.org.
The Chinese could take control of some US root servers at various universities, but it would be kind of obvious and pretty easy to mitigate. The Chinese could infiltrate ISPs and do blocking, redirection, and/or various types of spying which would be less easy to detect. They would just need some strategic insiders.