Awesome! But this isn't a garden, it's just lawn and trees. You'd have to mow the lawn and trim the hedges, that's all.
"Garden" is when you think carefully what to plant and where, what loves sun and what can live in a shade, when the blooms come and how to combine different colours, whether you like to attract insects, or love scented plants and shrubs. Gardening is also about aesthetics, not just maintenance, and the bigger the space to fill the more time and money you'll need if you want to create an amazing garden.
This property has a clean modern look, and the minimalistic (yet huge) garden reflects it. It's not going to be as much work as in, say, traditional "English cottage garden".