[As a Buddhist, we should be compassionate towards the beings in the lower 3 realms, including the ghost realm. Instead of thinking of exorcism or chase them away, our thoughts should be to help them get out of suffering in the lower 3 realm.
The story below from Pali Canon. Please read the last part if you do not want to read the whole story. This practice is known as transfer of merits 回向]
Petavatthu(Ghost stories)2.7 Dhanapala, The Rich Merchant
https://tipitaka.fandom.com/wiki/Petavatthu(Ghost_stories)2.7
While the Teacher was staying at Jetavana, he told this story.
Before the Buddha was born, there was in the kingdom of Dasanna in the city of Erakaccha, a rich merchant Dhanapalaka, who was unbelieving, irreligious, mean and heretical. His works can be understood from the following text. At his death he was reborn as a peta(ghost) in a desert wilderness. Tormented by hunger and thirst, he wandered here and there.
So in the time when Buddha was born in the world and had started illuminating the Dhamma(path), some merchants who lived at Savatthi filled five hundred wagons with goods, and having gone to Uttarapatha(north India), sold their merchadise. There then they loaded on their carts goods for the return journey. They set out on the homeward road and at evening arrived at the foot of a certain tree. Then they unharnessed their oxen and made their abode for tile night: Then that peta, who was tormented by thirst, came to that place to get something to drink, and not obtaining even a drop, he uttered a cry. When the merchants saw him, they asked him:
1. "Naked and of hideous appearance are you, thin and
with your veins visible. Your ribs stand out, and you are
emaciated. Now who are you, sir ?"
The peta:
2. "I, venerable sirs, am a peta, an unfortunate denizen of
Yarna's world. Since I had done evil I went from this world
to the region of the petas."
The merchants :
3• "Now what evil was done with your body, speech, or
mind ? Because of what act have you gone from here to
the world of the petas?"
The peta:
4• " There is a city of the Dasannas, famous, known by
the name of Erakaccha. There I formerly was a rich merchant;
by the name of Dhanapala they knew me."
5. "Eighty cartloads of gold belonged to me; I had
abundant gold and many pearls and cat's-eye gems."
6. " To such an extent was I the owner of great wealth,
but I did not like to give. When I took my meals, I locked
my door so that the beggars should not see me."
7, " Unbelieving and miserly was I, avaricious and abusive;
I used to restrain many of those who were charitable and
were active, "
8. "Saying: ' There is no reward for giving. Where is the
fruit of self restraint ?"
"The lotus-ponds, the wells, and the planted pleasure
gardens, the wayside watering places, and the passages at
the place hard to cross, I have destroyed."
9. "So I , not virtuous in my deeds, left the world as an
evildoer. I was reborn in the peta-region and am afflicted
with hunger and thirst. It is fifty-five years since I died."
10. " I do not recognize either food or drinking water.
As the withholding so is the loss, so the withholding.
For the petas , they say, know it : 'As the withholding
so is the loss'
11. "I, in the past, withheld; I did not give away many
treasures. Although deeds of charity are a duty, I did not
provide a refuge for myself."
12. " Now I feel bitter remorse, and I am burdened with the
fruit of my own deeds. After four months will come my death."
13. Down to the exceedingly severe and terrible hell I
shall fall ; it is four-cornered and has four doors; it is divided
into parts by measure; it is surrounded by an iron fence and
is covered on the top with iron."
14. "Its iron floor is glowing with heat. Flashing in all
sides for a hundred yojanas(x8km). it stands for all time."
15. "There for a long time I shall experience grievous
pain and the fruit of my evil deeds. Therefore, I bewail
this reality."
16. "For this reason I tell you something excellent, all of
you who a assembled here; do not commit a sinful act
either openly or in secret."
17. "If this evil deed you do or will perform, grief will
not leave you, even though ,you fly up in the air to escape it."
18. "Be respectful to mother and father; in the family
honor the elders ; give reverence to monks and brahmans(illuminated).Thus
you will come to heaven,"
19. "Not in the sky nor in the middle of the ocean, not
even though one enter the caves of the mountains, is found
that region of the earth where one could stand and free himself
from his evil deeds."
The merchants felt sorry for him and sprinkled water in his mouth. But, on account of the wicked deeds of that peta(ghost), he could not swallow. They asked him; "Now can't you get just a little relief ? "
He replied ; " Yes, when this evil deed is destroyed.
If a donation be given either to Tathagata(Buddha) or to the disciples of Tathagata(Buddha) and the virtue of the donation be transferred to me, then I shall be released from this peta existence."
When the merchants had heard him, they went to Savatthi and told the Buddha, gave for seven days a great donation to the Sangha of the monks there, at whose head was the Buddha, and ascribed the gift to the peta. Buddha then gave those merchants a dhamma discourse and the wise advice of staying away from the evil of greed & miserliness and instead follow the path of donation and of good deeds.
Pure Land Buddhism
