i would like to practice georgian, can help with russian & english

This is american english. In the UK we dont call them principals, we call them head teachers.

პატარა განსხვავებებს თუ არ ჩავთვლით მენეჯმენტის მხრივ ჩვენებურად დირექტორი;)

good luck my friend

The principal of a school is the person in charge of the administration of the school. It's similar to a manager (they are the boss of the school). The are the main authority in the school and make decisions about how to run things day to day. I hope this helps.