A published interview can be cited in a similar style to an article. Include the name of the person being interviewed then the person conducting the interview with the word "by" in front of it. If it is an online interview include the URL. If it is an unpublished interview that you personally conducted in person or over email or texts it only needs a footnote citation.
Bibliography Example (Published Interview)
Beckham, Victoria. "Victoria's Secrets." Interview by Laura Brown. Harper's Bazaar, (December 3, 2008): 268-279.
Noguchi, Isamu. "Father and Son: A Conversation with Isamu Noguchi." Interview by Yoshinobu Hakutani. Journal of Modern Literature 17, no. 1 (1990): 13-33. http://www.jstor.org/stable/3831400.
Footnote Example (Published Interview)
1. Isamu Noguchi, "Father and Son: A Conversation with Isamu Noguchi," interview by Yoshinobu Hakutani, Journal of Modern Literature 17, no. 1 (1990): 13-33. http://www.jstor.org/stable/3831400.
Footnote Example (unublished Interview)
1. Calvin Klein, interview by author, July 22, 2019.