i guess you didn't read. i will try to explain again.
a clutch is allowed to engage & disengage an engine to stop or start. after it is moving it isn't.
if you know how to drive stick you know that every time you change a gear you need to press the clutch.
china girls with a clutch are like an automatic car because an automatic car has a neutral.
that is what our clutch does. it makes a neutral.
even with a shift kit we don't use the clutch.
now back to the bike you linked.
you don't have any control over the engine. it has modes.
you press a button then ride it as a normal bike.
.to the strain on the cyclist, it has to determine how much auxiliary power is needed. For this purpose, three sensors measure speed, pedaling frequency, and torque. These allow the optimum amount of mechanical support to be computed. For example, if a head wind comes up, the e-biker must pedal harder to maintain the same speed. The pedal-force sensor reacts to this, and extra power from the motor makes up for the additional strain. This technology wastes no power, making the Bosch Drive Unit extremely efficient.
you have no control like a throttle. it is automatic.
also
After accelerating to 25 kph in just a few seconds, the motor automatically shuts off.