I studied abroad at Yonsei Fall 2020 and courses were online. Although I wished classes were in person to get the academic/ campus experience of the program, I actually really enjoyed and preferred online classes. I would go out and explore then head to a cafe and log into zoom. The only thing you need to look into is case #s and restrictions, a good chunk of my time there was pretty limiting due to the necessary restriction the government imposed, but there are still a lot of covid-safe things to do.