A control device comprising: a learning device comprising: a data acquisition unit configured to acquire, before control of a control target provided in equipment by a machine learning model that outputs an action corresponding to a state of the equipment, initialization data including state data indicating the state of the equipment and action data indicating an action on the control target; wherein the state data include operation data indicating a process variable of the control target measured using sensors of the equipment and a manipulated variable used to control the control target, and the action data is the manipulated variable change amount; and a preliminary learning unit configured to initialize the machine learning model by performing preliminary learning on a basis of the initialization data before start of reinforcement learning of the machine learning model, wherein the learning device further comprises an extraction unit configured to extract sample data to be used for initialization of the machine learning model from the initialization data, wherein the extraction unit includes a definition unit configured to define an option for the machine learning model to choose the action, the extraction unit is configured to extract, as the sample data, a combination of the state data included in the initialization data and the action included in the option, and the definition unit is configured to define the option on a basis of a distribution of actions indicated by the action data included in the initialization data that is acquired from data obtained when the control target is subjected to a feedback control or a manual control, and the control device further comprises a control unit configured to control the control target, which is an actuator controlling a physical quantity of the equipment corresponding to the manipulated variable change amount, by the machine learning model. a learning device comprising: a data acquisition unit configured to acquire, before control of a control target provided in equipment by a machine learning model that outputs an action corresponding to a state of the equipment, initialization data including state data indicating the state of the equipment and action data indicating an action on the control target; wherein the state data include operation data indicating a process variable of the control target measured using sensors of the equipment and a manipulated variable used to control the control target, and the action data is the manipulated variable change amount; and a preliminary learning unit configured to initialize the machine learning model by performing preliminary learning on a basis of the initialization data before start of reinforcement learning of the machine learning model, wherein the learning device further comprises an extraction unit configured to extract sample data to be used for initialization of the machine learning model from the initialization data, wherein the extraction unit includes a definition unit configured to define an option for the machine learning model to choose the action, the extraction unit is configured to extract, as the sample data, a combination of the state data included in the initialization data and the action included in the option, and the definition unit is configured to define the option on a basis of a distribution of actions indicated by the action data included in the initialization data that is acquired from data obtained when the control target is subjected to a feedback control or a manual control, and a data acquisition unit configured to acquire, before control of a control target provided in equipment by a machine learning model that outputs an action corresponding to a state of the equipment, initialization data including state data indicating the state of the equipment and action data indicating an action on the control target; wherein the state data include operation data indicating a process variable of the control target measured using sensors of the equipment and a manipulated variable used to control the control target, and the action data is the manipulated variable change amount; and a preliminary learning unit configured to initialize the machine learning model by performing preliminary learning on a basis of the initialization data before start of reinforcement learning of the machine learning model, wherein the learning device further comprises an extraction unit configured to extract sample data to be used for initialization of the machine learning model from the initialization data, wherein the extraction unit includes a definition unit configured to define an option for the machine learning model to choose the action, the extraction unit is configured to extract, as the sample data, a combination of the state data included in the initialization data and the action included in the option, and the definition unit is configured to define the option on a basis of a distribution of actions indicated by the action data included in the initialization data that is acquired from data obtained when the control target is subjected to a feedback control or a manual control, and the control device further comprises a control unit configured to control the control target, which is an actuator controlling a physical quantity of the equipment corresponding to the manipulated variable change amount, by the machine learning model.