Can monotheism be proved Biblically?

Mark 12: 32 "For there is one God, and there is none other but He."

1 Timothy 2: 5 "For there is one God, and one mediator between God and man, the man Christ Jesus."

Isaiah 44: 6 "Thus saith the Lord, the King of Israel, 'I am the first, and I am the last, and beside me there is no God.'"

The scripture teaches us - have I not told you that ye are gods therefore choose good or choose evil - but know one should choose you to be their God. I believe that all human kind are deity even Sons and Daughters of the Most High God, the eternal Father. I guess I am saying, yes, there are many gods; however, I choose to obey only one, a masculine Deity, which is the Most High, and what's more, only give him my worship - this is my belief

Yes it can. The trinity dogma is not Scriptural. It is a man made dogma from about the third century onward.

In the Bible, Jesus himself spoke of God as being another person besides himself, in John 17:3, where it is mentioned: "you, the only true God, AND of the one whom you sent forth, Jesus Christ."

Also in Revelation 3:12 Jesus 4 times speaks of "my God."

So, he is not the one true Almighty God.

However, the Bible does allow for the existence of other gods, even including money, our own belly, etc.

Satan is called the god of this world in 2 Corinthians 4:4.

Back when that was written, the majority of ancient societies believed in a mulitude of different gods and goddesses. God was telling the Hebrews that he did not want to have to compete for their affections.

"Thou shalt have no other Gods before me" shows that the ancient Hebrews thought that other gods existed and the priesthood feared that their people might relegate Yahweh behind another deity or two.