Change FOREIGN KEY Reference in sql

try this sample way for

the
ALTER TABLE Dealpool ADD CONSTRAINT fk_Dealpool_Agent FOREIGN KEY (AgentId)

//It is a reference table column

REFERENCES Agent(AgentId) // It is a referring  table primary key


Below final code is .

ALTER TABLE Dealpool ADD CONSTRAINT fk_Dealpool_Agent FOREIGN KEY (AgentId)    REFERENCES Agent(AgentId)