15 He is the image of the invisible God, the firstborn over all creation.-Colossians 1:15 HCSB
In the next verse, it shows Jesus as the Creator of the universe.
16 For everything was created by Him, in heaven and on earth, the visible and the invisible, whether thrones or dominions or rulers or authorities— all things have been created through Him and for Him.-Colossians 1:16 HCSB
In Isaiah 44:24, it says, “This is what the LORD, your Redeemer who formed you from the womb, says:
I am Yahweh, who made everything; who stretched out the heavens by Myself; who alone spread out the earth”
The LORD alone created the universe without any help as also seen in Genesis 1:1. Jesus in John 1:1 is revealed as God, and in John 1:3, He is the Creator. For Jesus to be the Creator, He has to be God as God alone created the universe.
The word “firstborn” in Colossians 1:15 is not used in a literal term as in being born or created, but it is used as having preeminence which that is the other meaning of the word. The meaning of the word is found in its context, see below.
18 He is also the head of the body, the church; He is the beginning, the firstborn from the dead, so that He might come to have first place in everything.-Colossians 1:18 HCSB
So, in verse 15, it does not show Jesus as a created being, but that He has preeminence of all things for who He is, the Creator of the seen and unseen world, and the first to resurrect from the dead (1 Corinthians 15:20) with a spiritual body which all the saints will have after their bodily resurrection (1 Corinthians 15:50-56).