No. An abbreviation is any shortened form of a word or phrase used in place of the whole (for example, Dr. for doctor or amt for amount). An acronym is a narrower kind of abbreviation formed from the initial letter or letters of the parts of a compound term—often pronounced as a word, such as NATO, scuba, or radar.
Merriam-Webster also notes that everyday usage sometimes labels letter-by-letter forms like FBI as acronyms; linguists often call those initialisms. Either way, many abbreviations (including clipped words and conventional shortenings) are not acronyms.
Source: Merriam-Webster — What’s an acronym?.