An electronic apparatus, comprising: a communicator; a storage configured to store password information including at least one character; and a processor configured to: select a plurality of different words respectively representing a plurality of characters based on occurrence of a password input event, transmit the plurality of selected words to a terminal device through the communicator, and cause the electronic apparatus to: based on a difference between a reception time of a first word of a user voice and a reception time of a second word of the user voice being within a predetermined period of time, combine a first character represented by the first word with a second character represented by the second word according to a reception order of the first word and the second word, and perform a function corresponding to a password authentication based on a string of the combined first and second characters matching the password information, wherein the user voice being received includes the first word and the second word among the plurality of selected words, and based on the difference between the reception time of the first word and the reception time of the second word exceeding the predetermined period of time, perform the function corresponding to the password authentication with each of the first character and the second character, based on each character matching the password information. a communicator; a storage configured to store password information including at least one character; and a processor configured to: select a plurality of different words respectively representing a plurality of characters based on occurrence of a password input event, transmit the plurality of selected words to a terminal device through the communicator, and cause the electronic apparatus to: based on a difference between a reception time of a first word of a user voice and a reception time of a second word of the user voice being within a predetermined period of time, combine a first character represented by the first word with a second character represented by the second word according to a reception order of the first word and the second word, and perform a function corresponding to a password authentication based on a string of the combined first and second characters matching the password information, wherein the user voice being received includes the first word and the second word among the plurality of selected words, and based on the difference between the reception time of the first word and the reception time of the second word exceeding the predetermined period of time, perform the function corresponding to the password authentication with each of the first character and the second character, based on each character matching the password information. select a plurality of different words respectively representing a plurality of characters based on occurrence of a password input event, transmit the plurality of selected words to a terminal device through the communicator, and cause the electronic apparatus to: based on a difference between a reception time of a first word of a user voice and a reception time of a second word of the user voice being within a predetermined period of time, combine a first character represented by the first word with a second character represented by the second word according to a reception order of the first word and the second word, and perform a function corresponding to a password authentication based on a string of the combined first and second characters matching the password information, wherein the user voice being received includes the first word and the second word among the plurality of selected words, and based on the difference between the reception time of the first word and the reception time of the second word exceeding the predetermined period of time, perform the function corresponding to the password authentication with each of the first character and the second character, based on each character matching the password information. based on a difference between a reception time of a first word of a user voice and a reception time of a second word of the user voice being within a predetermined period of time, combine a first character represented by the first word with a second character represented by the second word according to a reception order of the first word and the second word, and perform a function corresponding to a password authentication based on a string of the combined first and second characters matching the password information, wherein the user voice being received includes the first word and the second word among the plurality of selected words, and based on the difference between the reception time of the first word and the reception time of the second word exceeding the predetermined period of time, perform the function corresponding to the password authentication with each of the first character and the second character, based on each character matching the password information.