Where was Nathaniel first mentioned in the Bible?

Answer 1

I think you mean Nathanael. He was also known as Bartholomew.

(Matthew 10:3) Philip and Bar·thol′o·mew; Thomas and Matthew the tax collector; James the [son] of Al·phae′us, and Thad·dae′us;

(Mark3:18) and Andrew and Philip and Bar·thol′o·mew and Matthew and Thomas and James the [son] of Al·phae′us and Thad·dae′us and Simon the Ca·na·nae′an

(Luke6:14) Simon, whom he also named Peter, and Andrew his brother, and James and John, and Philip and Bar·thol′o·mew,

(John1:45, 46) Philip found Na·than′a·el and said to him: "We have found the one of whom Moses, in the Law, and the Prophets wrote, Jesus, the son of Joseph, from Naz′a·reth." 46 But Na·than′a·el said to him: "Can anything good come out of Naz′a·reth?" Philip said to him: "Come and see."

(John1:42) He led him to Jesus. When Jesus looked upon him he said: "You are Simon the son of John; you will be called Ce′phas" (which is translated Peter).

(Mark10:46) And they came into Jer′i·cho. But as he and his disciples and a considerable crowd were going out of Jer′i·cho, Bar·ti·mae′us (the son of Ti·mae′us), a blind beggar, was sitting beside the road.