Question

price controls on goods can be set by

Answer 1

Library of Economics

Answer 2

I am assuming that you mean to ask how can price be controlled.
For diffrent markets the answers are somewhat different.
In a monopoly,the seller can decide the amount of money to charge for its product/services.
Thus it is essentially controlling the price.
In general , government can put price ceilings or price floors(you cannot charge above price ceiling or below price floor)to control prices.

As a side note this often leads unwelcome results.When price is controlled,demand generally does not meet supply.Therefore market has to come up with another mechanism to allocate resources.Hence we saw long lines outside petrol pumps etc. when in history petrol prices were tried to be controlled by government.In essence the people were paying,not cash but their time.
And this inefficient.