Pizza is the food of teenagers so first night arriving - do pizza for her. Even if its late get her a smile pizza and then if she is hungry she has food in her belly for sleeping after a long day travelling.
Ask if there is any food that she can't or doesn't like - then make dishes around that. My Spanish students loved sweet and sour chicken, hot chocolate and bread dipped in the hot chocolate for breakfast. After a week of cooking, ask what her favourites were from that week and carry them over and make again.
Make sure her mobile phone works in your country and give her the wifi code. I am usually hosting 17 year old now, but ensure that they know to text me when they leave scollege, text me when you get on the bus and text me if you get lost - so make sure they have your phone number. Be clear on what time dinner is and what time you expect them to return home if they are allowed out alone.
Let her know when she can use the bathroom for showering and how long for. if there are 4/5 people all trying to get in the bathroom in the morning then its easier to give a time slot so she feels comfortable and n=knows its her time and what is expected of her.
Ensure if she goes out that she is not drinking alcohol. I have had a student where someone in her group got very drunk in the park as they had managed to buy cider.
My Japanise students always wanted to help so I would get them to lay the table for dinner and help load the dishwasher and clear the table, they are part of the family so them helping is fine and makes them feel part of the family.
I have a book for students to write in about their stay, any advice for the next person staying and what foods they liked - all this is written in their own language.
I always give them a snack to take to college in case they missed breakfast, especially the girls - I usually make croissants from frozen and wrap up.
We watch Netflix with subtitles as its easier for them to follow.
remember they will be far more nervous than you