No, this will be a device somewhere inside the home. One side is connected to your home’s AC (~110-120 V) and then the transformer steps the power down so that the load side outputs lower voltage (typically ≤24 V). Mine looks like this:
It’s in the upper-right corner of the image. I was demonstrating a test of its voltage at the time, so you see red and white wires (going to the chime box) attached to the transformer’s load terminals, and you see red and black wires (from the multimeter’s leads) attached to those same terminals for testing. Note that this is a side view of the transformer, which is mounted to the bottom of a junction box. For links to other photos with frontal views, you can look at What is the recommended transformer for a Wyze Duo Cam doorbell?, or you can do an image search for doorbell transformer with your preferred search engine to get an idea of what to look for.
It could be located pretty much anywhere in the home, but typically you’ll see it at, near, or attached to a breaker box or in a mechanical room (like where a home’s furnace and water heater might be; the basement in my case). Some Forum users have reported that theirs are in attics or closets. Sometimes it’s even in a wall directly behind the chime box.
If you think you have everything wired correctly but don’t yet have an easy means to test the voltage at the Duo Cam Doorbell’s location, then tracking down the transformer would probably be my next step (but I’d still really want to test at some point). If you know which breaker controls power to your doorbell, then that might provide a clue about where to look for it.
Feel free also to post photos of any parts of your installation (transformer, chime, etc.). Good visuals can help others in the community who want to assist with troubleshooting.