You need a controller for sensorless motors.
There's an important thing you need to consider. If you want to use a pedal sensor for pedal assist, there's basically 3 options:
1. No LED/LCD control panel. Cheaper, but when you pedal, you only get maximum power, which is not always what you want.
2. LED control panel. You get 3 levels of pedal assist -low, medium and high.
3 LCD control panel. More expensive but you get 5 levels of assist plus all the cycle computer functions plus a lot more.
Your motor is rated at 250w, which is 7 amps continuous. You can go as high as 22 amps with sensible use. You can't turn it up to maximum and then go and climb a one mile hill. It would be OK for a short steep hill or continuous high speed . Motors are much happier at high speed than low speed.
There's three sensorless controllers that I know and can recommend:
S06P from BMSBattery. You have to buy one of their LCDs too, and probably a good idea to buy the throttle, PAS and wheel-speed sensor to go with it.
S09P is the same but 22A instead of 15A. It's a bit bigger too.
This one from aliexpress is 14 amps but relatively cheap. It's very versatile and works with all motors. It comes with an LCD.
https://www.aliexpress.com/item/24v36v48v250w350w-controller-LCD-display-manual-control-panel-dashboard-for-electric-scooter-ebike-moped-mtb-tricycle-dualmode/32464390144.html?spm=2114.13010608.0.0.r144au
I would wait until you have the motor before ordering a controller in case it turns out that it's sensored.
