Childproof Door Lever Lock Baby safety locks for doors (2 Pack) Improved door safety for kids, 3M Adhesive No Drilling Child Safety Door Handle Lock. Simple Install, No Tools Needed (White, 2)

Before your fence is installed you can childproof your door handle with something like this https://a.co/d/0d0TmEfW. I’d do that ASAP, you may even be able to find a similar device at a hardware store or Target even. You could also install an interior lock higher up where she can’t reach. And a door alarm just in case. 15 months is old enough to open the door & way too young to trust going anywhere near the pool alone.

When I had elopers, I was allowed to get these door locks for my doors. They also have some that go under the latch so the kids can’t pull them down but they’re not technically locked because you can open them by pulling the handle up.