score:4
You can look at https://travelbans.org/crossing-rules/?from=Thailand to see which countries are accessible from Thailand, or https://www.iatatravelcentre.com/international-travel-document-news/1580226297.htm to check each country one by one. There are a few other websites mentioned on Is there any website or service for showing countries / regions open for travel during Covid-19 restrictions?
Anyway I'm in the same situation (in Bangkok and trying to avoid going into the western covid-full countries) and from I can see all countries in East Asia are currently closed to tourists who doesn't have some Asian passports. Indonesia at some point had hinted they'd reopened in September but the plan seems to have been reversed. This is reckless from governments to force people to exit covid-free countries, but that's no surprise since the covid-19 pandemic is mostly a stupidity pandemic.
Screenshot of https://travelbans.org/crossing-rules/?from=Thailand (mirror 1, mirror 2):
FYI South Korea isn't currently open to tourists:Ā Can French citizens apply for a South Korean tourist visa with the ongoing COVID-19 travel restrictions?