Um. Anything the both of you enjoy doing could be considered a date, technically, if you plan it ahead of time and it has some romantic part to it. Though it doesn't have to, I guess. Mostly I just like spending time with whoever I'm dating and I don't care that much about the how or where.
You could take her to dinner, anywhere on the planet thanks to portkeys. Or cook dinner for her. You could take her out to see a movie. Or a play. Most women like some type of flowers. You could even go for a walk in some city and talk for awhile? Um. Picnics are a bit sappy but they work cause it usually shows her you've spent a lot of time thinking about it. There's amusement parks, zoos, things like that if you want to go for a more creative approach. Does any of this help?