The one of big holiday of Korea, normally 3 ~ 4 days off.
meaning is “begin, start”, meaning is “day”, so Seollal meannng is new year’s day.
Korean visit their hometown to be with family.
Have time with family, talk about new year for each other.
Put on new clothes or best clothes.
Bows to elder.
Eat Ttokguk and ttokmanduguk.
Play Yut, fly kytes, spin tops and …
Seollal also make a lot of traffic jam. It you need to move, take trains and subway. It will be save your times.