which hotel will you stay ?
Hotel stuffs or hotel concierges service can make reservations famous sushi restaurant.
Hmmmm. Some sushi restaurants accept reservation online. But others(almost) accept phone call only. So you have to try anyway.
My advise is to use simple words, no complete sentence is necessary.
‘‘Reservation, July 15th , 7PM, three people (better than ‘person or ‘group of three etc. )
Email or fax can be much easier for them to understand.
They may ask your name and phone number.(they will not call back. )