I believe the widely accepted (but not universal) format for acronyms is all caps if each letter pronounced...for example MIT. Only the first letter is capitalized if hte acronym is pronounced as a word...for example Nasa.
Historically, MIT is not an acronym since it’s not pronounced as a word. MIT is just an abbreviation (specifically an initialism), while NASA is an acronym.
I don’t think there’s any rules about capitalization and acronyms, as scuba and laser are acronyms, and not capitalized, but NASA is. I’ve also never seen Nasa, it’s always all capitals NASA.