Do kids easy learn French?

Hi everyone! We will be moving to France and we have a 9 years old daughter who doesn’t speak French. She speaks Portuguese and English. We are planning to enrol her in a public school believing she will learn the language easier this way, but we don’t know if public schools in Paris and surroundings are used to take in kids that don’t speak French and then how they will treat her. I would like to know if any of you has experience with that and can share. Thank you!!