The Ford Model T had two forward speeds. Its planetary transmission provided low gear for starting and climbing, and high gear for normal driving.
The answer can seem confusing because contemporary descriptions often called the transmission “three-speed.” That count included reverse alongside low and high. In modern automotive language, reverse is not a forward speed, so the Model T is correctly described as having two forward speeds plus reverse.
The driver selected the transmission through a combination of pedals and a lever beside the seat. Pressing the left pedal with the lever in the appropriate position engaged low gear; releasing it allowed high gear when the lever was fully forward. The center pedal engaged reverse, while the right pedal operated the transmission brake.
This was not a conventional manual gearbox with a gear lever and synchronizers. The planetary arrangement let the Model T change between its useful driving ranges through pedal control. An optional auxiliary transmission or two-speed rear axle could add ratios, but those were aftermarket or specialized additions and do not change the standard Model T’s two forward speeds.