Well, Christians tend to disagree on a lot of events related to Jesus's second coming and the end of the world. The person who made the website seems to believe that the rapture happens first, then 7 years of chaos in which people still have the opportunity to be saved, then Jesus comes back.
Personally, I don't worry much about exactly what will happen at the end of the world; only that repentance and faith in Jesus Christ are how I can make sure that Jesus's Second Coming is a glorious day and not a horrific day for me. I also believe very strongly that no one will be sent to hell forever unless they choose to snuff out whatever goodness is left in them. As long as you have some good in you, it's not too late to be saved! Even though a lot of people will have to suffer, particularly those who delay their repentance for a long time, everyone who has good in them and doesn't snuff it out, will someday accept the gospel, repent, and be given a glorious eternity.
