@Jenn4657 Airbnb doesn't disclose a guests age. You may get an indication in a booking confirmation email that a guest is over 25, but that's it. You can stipulate that all guests must have verified id to book your listing.
https://www.airbnb.ca/help/article/1237/how-does-it-work-when-airbnb-verifies-your-identity
("Completing this process isn’t an endorsement of any host or guest, a guarantee of someone’s identity, or an assurance that interacting with them will be safe. Always use your own best judgment.." That part is important to keep in mind)
If you want all guests disclosed and added to the booking, make that a requirement in your house rules.