While students appreciate flexibility, you can set communication expectations about when your student comes home.
As you share your home, remember that you will likely be hosting young adults and they will appreciate flexibility as they explore this new place and adventure. Try to balance your needs and expectations with theirs as you work together to agree on house rules. Ensure your house rules contain information regarding when your student needs to contact you to let you know they won't be home for dinner, or for the night. You should also include information about being quiet when returning home late, locking the door, and any other expectations.
With high school student and younger, you may set a reasonable curfew and discuss it with your student when you discuss your house rules. There are also usually local curfew laws in place that students are also expected to abide by.