What happens in the after life to those who never heard about Jesus?

Matthew 1:1-16 the genealogy of Jesus… Abraham -Joseph.. 2Sam 7:12 the Davidic covenant God says I will raise up your offspring after you who shall come from your body and I will establish His Kingdom .. this is referring forward to the coming Christ. But Jesus did not come from the actual seed of these men in the lineage .. from their actual body … he was ‘adopted’ by Joseph who was the husband of Mary.. so the actual ‘seed’ bloodline should be Mary’s (I know that although hers is not outlined in scripture like Joseph’s in Matt 1, but I have heard in sermons that hers also goes back to Abraham.) How can we say he is the ‘seed’ when he wasn’t in the physical line of genealogy.

is fasting on a weekly basis instilled by the church biblical please?

.Please explain the devine
nature of God .."The Father. the Son and the Holy Spirit. Three
in One Person and why some people beleive,..God is one in
three Persons ..? . .