2 Peter 3-5 speak of the Earth ending by Water, correct?

The reference there was to Noah's Flood. Fire is the expected, future  method.

2 Peter 3:5 is speaking of the world that was. "The heavens were of old..."

Read verse 6, notice it states "the world that then was" not the world that is or that is to come.

That event happened before man was created on the earth.

2 Peter 3:6 “Whereby the world that then was, being overflowed with water, perished:”

(Psalm 37:9-11) For evil men will be done away with, But those hoping in Jehovah will possess the earth. 10 Just a little while longer, and the wicked will be no more; You will look at where they were, And they will not be there. 11 But the meek will possess the earth, And they will find exquisite delight in the abundance of peace.

(Psalm 37:29) The righteous will possess the earth, And they will live forever on it.

PETER'S name was plagiarized(Peter did not write them) on two epistles, 1 Peter & 2 Peter.

Ecc_1:4  One generation passeth away, and another generation cometh: but the earth abideth for ever.

Believe the Word of God, and not what humans teach.

God already promised He would not destroy the Earth with water ever again, that is what the Rainbow is to remind us of.

However God never said that He would not destroy the Earth with FIRE, which is what He is going to do during the 7 Year Tribulation Period. He is going to purge the Earth, and purge/destroy all unbelievers with it.

No, God has specifically told us that even though the earth suffered the terrible Noah flood previously, (1 Peter 3:20) - yet in the final Day it will NOT be water but FIRE next time.  "The Day of the Lord will come as a thief in the night in which the heavens shall pass away with a great noise and the elements shall MELT WITH FERVENT HEAT and the earth also and the works that are in it shall be BURNED UP.  Seeing then that all these things shall be dissolved, what manner of persons ought you to be in all holy conversation and godliness, looking for and hastening unto the coming of the day of God, wherein the heavens, BEING ON FIRE shall be dissolved, and the elements SHALL MELT WITH FERVENT HEAT.......... etc"  2 Peter: 3: 10 on)

This a recounting of the flood of Noah, nothing more.

No, it speaks there in the past tense of how the world of Noah's day was flooded, ending the global wickedness that had arisen. Past tense, not future tense: "For this they willingly are ignorant of, that by the word of God the heavens were of old, and the earth standing out of the water and in the water: whereby the world that THEN was, being overflowed with water, perished." Then Peter goes on to explain that the present heavens and earth are reserved for fire of judgment and the perdition of ungodly men.

Go on to read through to verses 10 to 14 to show that it is not water that God will use in the judgment to come. And that once He has acted, there will be a new heavens and a new earth, in which righteousness will dwell.  Bear in mind that, after the flood of Noah's day, God promised that He would never destroy the earth by flood again - Genesis ch. 9.

My thoughts are that the Book of Genesis is directly contradicted by that.