The Unreached and Unengaged are those people groups who exist that have no access to the Gospel. There is no one currently trying to reach them. They are waiting for us, church. Their soul depends on us bringing the Gospel to them. The question we are asking is not will you go but can you go?

In Romans 10, Paul says,
[12] For there is no distinction between Jew and Greek; for the same Lord is Lord of all, bestowing his riches on all who call on him.[13] For “everyone who calls on the name of the Lord will be saved.”[14] How then will they call on him in whom they have not believed? And how are they to believe in him of whom they have never heard? And how are they to hear without someone preaching? [15] And how are they to preach unless they are sent? As it is written, “How beautiful are the feet of those who preach the good news!” [16] But they have not all obeyed the gospel. For Isaiah says, “Lord, who has believed what he has heard from us?” [17] So faith comes from hearing, and hearing through the word of Christ.
[Romans 10:12–17ESV]

Then just 5 chapters later, He says,
[20] and thus I make it my ambition to preach the gospel, not where Christ has already been named, lest I build on someone else’s foundation,
[Romans 15:20 ESV]