To estimate a force on a road, choose a sensible mass for the vehicle, choose a sensible acceleration, then use force = mass × acceleration. The answer only needs to be about the right size, so round the numbers.
A small car has a mass of about 1000 kg. Pulling away from traffic lights at about 2 m/s2 needs a resultant force of 1000 × 2 = 2000 N. In an emergency stop on a dry road the deceleration is about 8 m/s2, so the braking force is about 8000 N. A cyclist and bike with a combined mass of 90 kg, accelerating at 1 m/s2, need a resultant force of about 90 N.
A loaded lorry has a mass of about 30000 kg. Accelerating at only 0.5 m/s2 it needs a resultant force of 15000 N, much larger than for the car, because its mass is so large. At a steady speed the driving force equals the resistive forces such as air resistance and friction, so the resultant force is zero.