I have no idea what I'm doing

It was the first morning in my new home and I was sitting by the kitchen window with my coffee cup, staring outside and feeling pretty good about things. I let my eye wander across the expanse of white snow until it caught in the hedge.
"Wow, we have a hedge and all," I thought and sipped at my coffee with a smile. Then another thought struck: it'll probably need maintenance at some point. My smile slipped a little. Then it fell away entirely as I realised that I'd have to know what that maintenance was and when to do it.
"Halp," I thought, fighting a rising panic. "I have made a terrible mistake..."
--
I've never had a garden or a yard of my own before. When I moved from our flat to The New Place with my parents at the age of 14 (this was in 1986), we gained a little backyard that my mother especially liked to maintain, but my interest in it was about on par with my fascination with romance novels - i.e., nonexistent. When we began to house-hunt in late 2017 it took a while to realise that, if we wanted to live in a rowhouse or a semidetached house, a garden would be included in the deal. The Hubby wasn't too excited about the prospect, but hey, how hard can it be?
Right?