I guess you cannot connect your treadmill directly to Zwift - Zwift requires BLE and your treadmill only speaks bluetooth.
However, thats not a big problem, because Zwift only requires your actual speed. You can send your actual speed/the speed of the treadmill either via a Footpod (e.g. Stryd, Zwift RunPod) or a Sensor you stick on your treadmill (NPE Runn).
I personally own a smart treadmill and it is no big advantage, because the treadmill doesnot receive any input from Zwift. You have to adjust the speed and incline manually anyway.
I hope this helps, have fun,