Venezuela and Japan have the highest, but you forgot to mention the United States is 12th -"While the U.S. boasts the highest GDP in the world,, it nonetheless spends more than it earns. Major contributors to the national debt include the world's largest military budget, tax cuts (which reduce government income and rarely result in a corresponding increase in economic growth), COVID-19 relief efforts, and mandatory-but-underfunded programs such as Medicare."

Brunei and Afghanistan have the lowest. You need a better metric to make your pro neo liberal take💀

Source - https://worldpopulationreview.com/country-rankings/debt-to-gdp-ratio-by-country