Is the paternal uncle obligated to spend on his deceased brother's daughters from their inheritance, given that one of them works and the other wishes to study outside Egypt, and is he required to give them the full inheritance for that purpose?

A paternal uncle is not obligated to provide university tuition for his brother's daughters because it is not considered a mandatory expense. However, he is obligated to provide for their food, drink, clothing, and housing, subject to three conditions: that the niece is poor, that the uncle is able and has surplus beyond his and his dependents' essential needs, and that the uncle would inherit from her if she were to die. If any of these conditions are not met, the obligation to provide maintenance ceases.

Regarding the daughters' demand to their uncle for something from their father's inheritance: if what is meant is his share of the inheritance, then they have no right to it unless he is obligated to provide maintenance for them. If what is meant is their share, then that is their right. It is not permissible to use stratagems to deprive an heir of their share, for the division of inheritance is from Allah, and every heir must be enabled to receive their portion.