The instruments used to measure the forces are spring scales or force meters.
A spring is used to make a force meter. The spring is stretched by the force and returns to its original shape when the force is no longer applied. The more the spring stretches, the greater the force applied to it.
A force meter is pulled with a force 1 N, when a weight with a mass 100 g is hung on it.
Read the force shown by the force meter when the toy is dragged along the floor.
F = 0.4 N