I would check into Penn State. PA as a whole is very safe and the people are very friendly but like any country the bigger cities can be quite rough. Philly in particular is probably a lot worse than what you are used to in Europe especially with the scale of the poverty there. Penn State is in a small college town in the middle of the state and is wonderful, however I’m biased since I went there.

As far as the immigration stuff I’m really not sure if you can work on a student visa. I would suggest checking the department for international students at whatever university you are looking at.

https://global.psu.edu/international