The correct meaning of the phrase "the Beginning of the creation of God" is the Beginner or Author of God's creation. "Beginning" is a rendering of the Greek word archee, which refers to an originating instrument or active cause of origin (see Colossians 1:15-17). In his The New Testament in the Language of Today, William F. Beck translates this as "The Origin of God's creation." As the Creator or Originator of all things, Jesus is the Head and Governor of all creatures; He is the King of creation (see Psalm 148). For further discussion of this meaning, please see the commentary on this verse by Jamieson, Fausset, and Brown and the one by Adam Clarke.
Proverbs 8:22-31 is sometimes cited as evidence that Jesus was created. However, this passage is clearly referring to wisdom personified (see verse 1), not to God! Notice that God possessed wisdom in the beginning and used it in creating the worlds.
The Bible tells us plainly that Jesus (who many believe was Melchizedek—Genesis 14:18-20) had no beginning of days nor end of life (Hebrews 7:1-3). He was not created, but was the Creator of all things that were made (Colossians 1:16; Hebrews 1:2; 2:10). He was with the Father in the beginning, and all things were made by Him (John 1:1-3). He has always existed.