Dear bjupin1488:
If your surname is JUPIN, I regret that I am unable to assist you vert much. I have never managed to find any connection between people in the USA with the surname JUPIN and those with the surnames JUPINA or JUPENA. The latter two names are very definitely interconnected, however.
What I CAN tell you is that knowing that your grandparents came from "Hungary" is not very helpful, because in the late 19th and early 20th centuries both "Austria" and "Hungary" were used by American immigrants to refer to almost anywhere in the entire Austro-Hungarian Empire, which stretched from the farthest western parts of modern Austria across into parts of modern Ukraine in the East, and from Galicia (now part of southern Poland) in the north down into parts of Serbia and Macedonia. It is MUCH more likely that your grandparents actually came from somewhere in the modern Slovak Republic, which was then just one part of the Austro-Hungarian Empire. So far, everyone I am aware of with the family name JUPIN can actually trace their family back to a Slovak family that spelled the name as DZUPIN. I hope this is helpful.