I had a pet squirrel many years ago. He was injured when he was just a baby. My wife nursed him back to health after taking him to a wildlife vet. He lost his tail and one leg. He lived in the house with us along with a couple of dogs and a few cats and grew up to be a full fledged family member. We always left a window open for him and he spent most of the daylight hours outside but always came in for dinner and to sleep.
You can have a captive squirrel.
They tend not to be pet material.
Only if it's Secret Squirrel !
I think you can have a tame squirrel, but not a pet squirrel. It is still going to have its wild side and is still going to want to roam.
A squirrel can have a pet Human.
Learn to love.