there are little ferns growing all over our land (mainly under the shade of
the pine trees). If I were to dig a few up and put them in a hanging basket,
would they turn into one of those huge cascading ferns that you see in the
stores

No, they would probably drop dead. The fern you see in the stores is Boston
fern, whose original form is native to Florida. Wild hardy ferns need to grow
outdoors, usually in the shade, & most of them are rather fussy.
Iris,
Central NY, Zone 5a, Sunset Zone 40
"If we see light at the end of the tunnel, It's the light of the oncoming
train."
Robert Lowell (1917-1977)