What is the ruling on a girl traveling 200 km to study at university without a mahram, and what is the ruling on her visiting her grandfather's house, which is a distance from the university that requires her to take a bus alone? Is she obligated to wear the niqab and cover her hands along with wearing the jilbab? Is it permissible for her to greet or return greetings to male professors and students at the university? Must she consult her father on all her movements within the city, such as going to buy books or obtain documents? What is the ruling on her riding the university shuttle bus designated for female students if it is a few kilometers away from her residence?

A mahram (unmarriageable kin) is required for a woman's travel, not for her residence in another country if there is no fear of fitna (temptation/strife). Therefore, it is permissible for you to reside in university housing, visit your grandfather's house, and ride the bus to the university, as long as it does not constitute travel. Islamic law has not specified a particular type of hijab, but scholars have mentioned conditions for it. It is permissible to uncover the face when there is no fear of fitna. Mingling in universities is a reprehensible act, and if you are compelled to study, you must observe the etiquette of Islamic law, such as lowering your gaze and avoiding khalwa (private seclusion with a non-mahram). Initiating or returning greetings to non-mahrams is permissible when there is no fear of fitna. There is no requirement to seek your father's permission to go out to buy books or similar items that are free from suspicion, though it is preferable to inform him and seek his permission.