Do NASCAR cars have to be manual?

While modern day street cars are mostly automatic now, NASCAR requires that cars use a four-speed manual transmission.

Do Nascars have a clutch?

Because the clutch pedal is not a big part of a NASCAR race. Drivers use the clutch to get the car into first. But while hurtling around the track, most drivers just match the next gear to the engine RPM and shift without a clutch.