Does it exist?
What characteristics does it have?
How & when does a soul get attached to a particular human body?
Has the soul a special place in the body, does it reside in the heart, the brain, the liver,...?
Are the souls of men & women different (why & in which way)?
Do animals have souls?
Do plants have souls?
Is the number of souls limited?
Can the soul be touched by sin?
What happens to the soul after the body has died?
Is the soul affected by the way a body is buried (correct, incorrect)?
Can a soul die?
[Edit] Forgot one question: Can to souls unite to become one soul (for instance when 2 people marry)?
At the creation of Adam, after Adam received the breath of life, then Adam came to be a living soul.- Gen 2v7
According to Scripture then Adam existed as a living soul.
If obedient could remain alive as a living soul forever.
If disobedient would die and be a dead soul, or a destroyed soul.
When Adam died as a living soul, then Adam became a dead soul.
A dead soul or a lifeless soul.- Ecclesiastes 9v5.
Some souls have drowned at sea or burial at sea.
Doesn't matter because in the resurrection even the sea will give up its dead.
- Rev. 20v13 A.
As far as characteristics:
According to Leviticus [7 vs 18,20,25,27] the soul 'eats'.
According to Scripture Adam as a living soul did eat.
A soul can lust after something,- Deut. 12v15,20,21
A soul can be hungry and have appetite.
- Psalm 107v9;Proverbs 19v15; 27v7; Isaiah 29v8; 32v6; Micah 7v1
A soul can be thirsty.- Proverbs 25v25
A soul can be made fat according to Proverbs 11v25
A soul can diet or do fasting according to Psalm 35v13
A soul can touch the dead.- Lev. 5v2;7v21;17v15; 22v6
A soul can can be touched by sin.- Lev. 6v2; Ezekiel 18vs4,20
A soul can work.- Lev. 23v30
A soul can be destroyed.- Lev.23v30; Acts 3v23
A soul can be purchased.-Lev. 22v11
A soul can be sleepless.- Psalm 119v28
A soul can die.- Ezekiel 18vs4,20; James 5v20
A soul can be resurrected out of hell [sheol] Psalm 16v10; Acts 2vs27,31,32
Animals do Not have souls because animals like people are souls.
- Numbers 31v28 Plants are not souls, nor possess a soul.
Souls do not unite. Each person [or animal] is its own separate soul or person.
So, the 'biblical soul' is the person himself.
The non-biblical myth is the teaching of an immortal soul or death-proof soul.
The dead soul or person can be resurrected to heaven [Rev 20v6;5vs9,10],
or be resurrected on earth during Jesus 1000-year reign over earth when all the dead souls [persons] in the 'biblical hell' [sheol], which is the common grave of mankind, will be 'delivered up' [resurrected] out of the common grave and then vacant, emptied-out hell is cast into a symbolic second death.
-Rev. 20vs13,14.