Clutch disc is not being fully disengaged.
Look at the clutch fluid reservoir in the engine compartment, make sure it is full.
If it isn't then you may have some air in the system.
When you press the clutch pedal down the Master cylinder pushes fluid down the hose and into the Slave cylinder, Slave expands and pushes on the pressure plate which releases the clutch disc from the flywheel.
Hydraulic fluid(like brake fluid) is used because it doesn't compress under pressure.
Example: if you send 2" of travel down the hose then Slave will expand 2".
Air does compress, so if there is air in the system then that 2" becomes 1.5" and clutch disc is still touching flywheel so is still spinning, you have to force it stop spinning by pushing on shifter.
Google: Ford Ranger bleeding clutch