There are several differing views on this verse, I will form an answer based on the context of Paul's letter beginning with v12
Col 1:12 giving thanks to the Father, who has qualified us to share in the inheritance of the saints in Light. 13 For He rescued us from the domain of darkness, and transferred us to the kingdom of His beloved Son, 14 in whom we have redemption, the forgiveness of sins.
15 He is the image of the invisible God, the firstborn of all creation. 16 For by (rather through or in) Him all things were created, both in the heavens and on earth, visible and invisible, whether thrones or dominions or rulers or authorities—all things have been created through Him and for Him.
Clearly, even if we insist on 'by him', 'things ON earth and IN heaven' are not speaking of creation of all things. We must understand the passage with that fact in mind.
17 He is before all things, and in Him all things hold together. 18 He is also head of the body, the church; and He is the beginning, the firstborn from the dead, so that He Himself will come to have first place in everything.
v12 "qualified us to share in the inheritance of the saints" Paul is talking about the kingdom.
V13 rescued us from the domain of darkness, and transferred us to the kingdom of His beloved Son
Paul focus is on the Father, as in -
Giving thanks to, the grace of, His will, pleasing Him, His glorious might, rescued us...
Then moving to Christ, we have, redemption, forgiveness, the image of God etc.
That we have Paul's mention of "all things created... IN heavens and ON earth". Again, Paul is not talking about a Genesis creation. If Paul was intending to speak of the initial creation he wouldn't say it like this and the topic would be incongruous. As Paul testifies in all his writings, he knows of one God-the Father, and His son Jesus. And Jesus wasn't in the beginning - the logos was.
Paul is referring to a new creation. A theme Paul has championed.
Therefore, if anyone is in Christ, he is a new creation. The old has
passed away; behold, the new has come. 2 Cor 5:17 also Gal 6:15 (there are footings for this in Is 43, 65)
Paul did write of the Genesis creation in Rom 1 '...ever since the creation of the world, in the things that have been made...' but that is not in view here in Colossians.
So now we get to, "He is the image of the invisible God, the firstborn of all creation."
So we see that Jesus is not firstborn of a Genesis creation, but of this NEW creation. We are told he was born ~4BC, and there is no mention of Jesus prior to this except in allusion via prophecy, promise, and God's revelation of a man, a saviour, that will arrive when the time is right - even from Genesis 3.
Being foreknown 1 Pet 1:20 Foreknown by who? God. Why is Jesus foreknown by God? Because he wasn't yet existing, but God had planned that he would when the time was right. Acts 2:23
For He was foreknown before the foundation of the world, but has appeared in these last times for the sake of you
Jesus, according to the text, is born as a man. He is not unequivocally referenced anywhere that makes him also God. Certainly he is not mentioned in John 1:1-3. This is the logos John writes of and not Jesus. If he meant Jesus, that is what we would be reading. We do read that this logos became flesh and Jesus began to exist then.
The new creation begins under a new covenant - not of law and sin and death, but of life and spirit - of forgiveness and grace made possible through the one perfect sacrifice of Jesus. (Rom 8:2)
In Rev 4:5, Col 1:18 Jesus is called 'the firstborn of the dead'. Not the first raised from the dead - because he was not the first by any means in a physical sense. The word 'dead' is a collective sense here and refers to ALL mankind who are dead to sin - ALL men are dead to sin in the flesh and will stay that way except for God's plan through Jesus.
Jesus is the first to be raised from fleshly life to a new spirit life - in which all men may follow.
For as in Adam all die, so also in Christ all will be made alive. 1 Cor 15:22
And you were dead in your trespasses and sins Eph 2:1
(of course, he is speaking to the alive - but only alive in the flesh and now given the spirit as a gift to be with them - prior to that, they 'were' dead)
Jesus is the first to be re-born of the spirit. When he was flesh he was mortal and subject to death, in fact death was 'master' over him. Rom 6:9
It wasn't until Jesus was raised in the spirit that he had true life - immortal life.
For Christ...having been put to death in the flesh, but made alive in the spirit 1 Pet 3:18
This is the start of a new creation - the church, the 'eklesia' is the first step to being saved - those who are spiritually alive, but only by a down-payment, a deposit of spirit, called out to be God's people, God's witness of what is good and true. (put His Spirit in our hearts as a pledge of what is to come. 2 Cor 1:22)
In Jesus the new creation has begun - it cannot be held back for long - a process is running that will not stop until others will join Jesus in eternity with the Father - he is the firstborn of many brethren Rom 8:29
waiting for this time of renewal and of true life in the spirit - only possible now that Jesus has led the way through death and into the next life - by the grace of God, all men may follow him.
Only in Jesus the Christ are we made in the 'image of God' - we cannot be on our own as sin closed the path that the first Adam was on. Jesus IS the image of the invisible God, and we will be so in him, finally, when our change has come. Rom 8:29 again
He also predestined to be conformed to the image of His Son, for Him to be firstborn among many brothers.
And just as we have borne the likeness of the earthly man, so also shall we bear the likeness of the heavenly man. 1 Cor 15:49