What I’m seeing online when I look up the Samsung Galaxy A3 is a ~10-year-old phone that isn’t 5G capable, so I wonder if you mean the Galaxy A33 5G.
Unfortunately, most Android vendors don’t make this obvious or easy. If you’re not seeing clues in the phone’s settings (e.g., under System or About phone, depending on what your particular Android version shows), then you might have to resort to using a third-party app to help you figure that out. I’ve used AIDA64 in the past to do that.
My guess at this point is that you’ve got a device running 32-bit Android since it’s a Galaxy A series phone and that tends to be Samsung’s low-to-mid range for devices. Although the hardware itself may be 64-bit capable, my understanding is that the lower amounts of RAM manufacturers tend to build into these devices also leads them to loading 32-bit Android versions on them so that performance doesn’t suffer too much, and the amount of RAM on the device might also be a clue about the OS. Given that, you’re probably going to have to source an older Wyze app or a newer phone (if you want to run the current Wyze app).