They went down alive into the realm of the dead, with everything they owned; the earth closed over them, and they perished and were gone from the community. Numbers 16:33, NIV
A very dramatic scene! Wicked people falling alive as the ground split open under them. You just can't find many situations like this one either in the Bible or out of it.
Recently a man died when he and his bed fell into a sink hole. Same idea. By that I mean that the man did not go into a fiery nether region ruled over by a being with a point on his tail and with horns on his head.
Yet he, along with Korah, went into the Biblical abode of the dead. It is not a location deep inside the earth where people are tormented.
I am a believer in root words. Though I do not read either Hebrew, Aramaic, or Greek, I have access to the works of those who do. We all do. A good Bible store can sell you books on these sources. If you want to avoid traffic or can't get out, then Amazon and other online sources will send them to you.
So, if you are not certain of the meaning of a word, look up the original source. Strong's online does a great job and is free.
So Korah and his family went to what many call "hell". However, in reality they died on the day of that great subsidence and now await the Judgement Seat of Christ.
An often bypassed part of the Korah story is that though he and his followers died, their incense censors were holy unto God. They were to be saved and used in the tabernacle.
There are some people out there who are unfit to serve God, but their Bibles are still good and true.