The South Korean approach to home education during the pandemic appears to be primarily a patchwork approach. Existing resources have been expanded and new resources have been created as needed. Each school across levels may have different approaches to solving education needs, and sharing resources between schools is not uncommon. Resources and links are outlined below. One important factor to consider is that there are not a lot of websites blocked in South Korea (often only pornography, gambling, pro-North Korea, and similar sites are blocked) so remote education is not particularly affected by this issue.
South Korean Ministry of Education on Learning in the Pandemic
The Education Broadcasting Service (EBS)
Educators not using EBS services and programs to some extent may use any number of other approaches to remote learning, such as Zoom, video lectures uploaded to YouTube, other software for posting lectures and managing assignments, Google products, and other online media.
Higher Education and OpenCourseWare