I doubt the flight will unless you smile sweetly and look smart at check-in.
The hotel generally like to be informed at the time you book. Some hotels offer incentives for, honeymoons and main anniversaries like silver (25 yrs).
Depends who you booked through and when you booked, and if you mentioned it. Otherwise its up to the hotel, you may get a free bottle of sparkling wine on arrival in your room, or nothing at all.
Some hotels ask to see a copy of the wedding certificate these days, as so many people make things up. I am sure you're not.
Happy anniversary.