Nowhere in the Old Testament is Satan (as we know him today) ever mentioned. If you want to show me to be wrong, please post one verse at a time and let me deal with each.
Take your pick.
Now there are many other meanings as all words have a lexical range. But here are the passages that interpreters thought the usage was personal.
Further we see Jesus talk more about Satan than all other authors combined.
Strong’s Definitions
H7853; an opponent; especially (with the article prefixed) Satan, the arch-enemy of good:—adversary, Satan, withstand.
Look for the definite article prefixed in the Hebrew text. That's how the interpreters consistently avoided your mistaken exegesis.
1Ch 21:1
And Satan
H7854 stood up against Israel, and provoked David to number Israel.
Job 1:6
Now there was a day when the sons of God came to present themselves before the LORD, and Satan
H7854came also among them.
Job 1:7
And the LORD said unto Satan,
H7854 Whence comest thou? Then Satan
H7854 answered the LORD, and said, From going to and fro in the earth, and from walking up and down in it.
Job 1:8
And the LORD said unto Satan,
H7854 Hast thou considered my servant Job, that
there is none like him in the earth, a perfect and an upright man, one that feareth God, and escheweth evil?
Job 1:9
Then Satan
H7854 answered the LORD, and said, Doth Job fear God for nought?
Job 1:12
And the LORD said unto Satan,
H7854 Behold, all that he hath
is in thy power; only upon himself put not forth thine hand. So Satan
H7854 went forth from the presence of the LORD.
Job 2:1
Again there was a day when the sons of God came to present themselves before the LORD, and Satan
H7854came also among them to present himself before the LORD.
Job 2:2
And the LORD said unto Satan,
H7854 From whence comest thou? And Satan
H7854 answered the LORD, and said, From going to and fro in the earth, and from walking up and down in it.
Job 2:3
And the LORD said unto Satan,
H7854 Hast thou considered my servant Job, that
there is none like him in the earth, a perfect and an upright man, one that feareth God, and escheweth evil? and still he holdeth fast his integrity, although thou movedst me against him, to destroy him without cause.
Job 2:4
And Satan
H7854 answered the LORD, and said, Skin for skin, yea, all that a man hath will he give for his life.
Job 2:6
And the LORD said unto Satan,
H7854 Behold, he
is in thine hand; but save his life.
Job 2:7
So went Satan
H7854 forth from the presence of the LORD, and smote Job with sore boils from the sole of his foot unto his crown.
Psa 109:6
Set thou a wicked man over him: and let Satan
H7854stand at his right hand.
Zec 3:1
And he shewed me Joshua the high priest standing before the angel of the LORD, and Satan
H7854 standing at his right hand to resist him.
Zec 3:2
And the LORD said unto Satan,
H7854 The LORD rebuke thee, O Satan;
H7854 even the LORD that hath chosen Jerusalem rebuke thee:
is not this a brand plucked out of the fire?