fizz / phiz are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
fizz: (noun) an effervescent beverage (usually alcoholic).
phiz: NA
fizz: f·IH·z
phiz: NA
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)