Is my feeling of guilt and shortcoming regarding advising all disbelievers and disobedient Muslims in France—due to the knowledge I wish to convey to them—justified, and what should I do?

Your feeling of shortcoming indicates your concern for enjoining good and forbidding evil, so do your utmost in this according to your ability. We advise you to hasten the completion of your studies and leave the lands of disbelief, due to the saying of the Messenger, peace and blessings be upon him: "I am free of every Muslim who resides among the polytheists; their fires should not be visible to each other." The meaning of "their fires should not be visible to each other" is that a Muslim should distance himself from the polytheists as much as possible.