I learned that fallen angels,
What you have done is just scratch the surface of the matter , like in math there is a level for 5th graders and another level for each grade on up even into advanced collegiate levels , simple math is always there but math gets deeper as it gets more advanced and so does study of scripture .
You are a spirit being with a physical body and so are angels , so when angels came to earth where did they go ?, what did they do ? How does an angel possess a human so that it takes Jesus to cast it out , how can 2000 angels posses a man as the man Jesus confronted have? Simple answer they can't do it because they have a body of their own , but a demon/unclean spirit does not have a body and seeks to find one to posses
We all can find the definition of a word , but you have to look into it deeply to understand the applications .. I know you struggle with this so I won't overwhelm you with too much at a time , but consider this - God created mankind in His own image to become His family members to spend eternity with Him. In the time of the flood -I will put a conservative number of approx 1 billion people on earth at the time of the flood of Noah - Now something to think about -
God loves his creation of mankind and bestowed special characteristics on man that no other living being has been given -including the angels - but yet God was so angry at mankind that he decided to wipe them of the face of the planet . Now God who created the planet and all that is on it by speaking a word and it came to pass , being so angry at what had happened on earth that he would decide to kill everyone that He created in His own image , own likeness.
He told Noah to build an ark for his own family and the animals - God plans to kill every person and every animal and wipe them out entirely , now compare what is happening in our world today where we not only have people killing for robberies but people driving big trucks into large crowds of people to kill as many people as they can , shooting in Las Vegas , shootings in schools and churches and random bombings , flying jumbo jet airliners into big tall buildings all for the purpose to kill as many people as they can with no motive of stealing money or other valuables but just for the sake of killing as many people as they can for killings sake ,
In Noah's time it says people were corrupt but they did not have the ability to destroy the planet such as we do - what was it that they did that was so bad that God did not want to send Jesus as a sacrificial lamb and allow them forgiveness
Gen 4
And the LORD saw that the wickedness of man was great in the earth, and that
every imagination of the thoughts of his heart was only evil continually.
11And the earth was corrupt before God, and the earth was filled with violence.
יב וַיַּרְא אֱלֹהִים אֶת-הָאָרֶץ, וְהִנֵּה נִשְׁחָתָה: כִּי-הִשְׁחִית כָּל-בָּשָׂר אֶת-דַּרְכּוֹ, עַל-הָאָרֶץ. {ס}12 And God saw the earth, and, behold, it was corrupt;
for all flesh had corrupted their way upon the earth. {S}
יג וַיֹּאמֶר אֱלֹהִים לְנֹחַ, קֵץ כָּל-בָּשָׂר בָּא לְפָנַי--כִּי-מָלְאָה הָאָרֶץ חָמָס, מִפְּנֵיהֶם; וְהִנְנִי מַשְׁחִיתָם, אֶת-הָאָרֶץ. 13 And God said unto Noah: '
The end of all flesh is come before Me; for the earth is filled with violence through them; and, behold, I will destroy them with the earth.
Not just mankind but all flesh -animals don't corrupt themselves
Consider that Only Noah was considered worthy to escape the total destruction of the flood sent to wipe out all of mankind
The ark that Noah built was only big enough to house his family and 2x2 male and female animals
Flesh has corrupted their way upon the earth
think about that for a bit and ask yourself what was it that this corrupted flesh has done that the God of love that created mankind in his own image that they did not receive the consideration of forgiveness of their sins -
and only one man and his family was considered worthy to survive - When you corrupt the seed you corrupt the gene pool - that would be like someone pouring used motor oil in your milk and if they ask for forgiveness, do you keep that milk or throw it out and get new fresh milk that is not corrupted with a mix of used motor oil?