@vitorary90 said:
Want to get a list of original languages from the API and display them as a dropdown search
Read the title.
Want to get a list of original languages from the API ...

You can find the list here:
https://developer.themoviedb.org/reference/configuration-languages

... and display them as a dropdown search
Is there a way of doing so?
If possible, I would like the original languages' names to be localized to my own language.

We do not have the names of the languages in your language.
Only in English and in some cases in the original language.
This must be resolved on your side.

Thanks! I've noticed that the array I get only has languages like pt and not pt-br and pt-pt. I suppose that, for original languages, you make no distinction?

@vitorary90 said:
Thanks! I've noticed that the array I get only has languages like pt and not pt-br and pt-pt.
I suppose that, for original languages, you make no distinction?

Exactly.
The name of the languages is unique.
But it can be spoken in different countries.
Therefore, in many cases we must use the language-COUNTRY combination.

ar  Arabic 2 (AE+SA)
de  German 3 (AT+CH+DE)
fr  French 2 (CA+CH+FR) only CA and FR
ms  Malay 2 (MY+SG)
zh  Mandarin 3 (CN+HK+TW)
pt  Portuguese 2 (BR+PT)
es  Spanish 2 (ES+MX)

But I believe that in the future we should always use language-COUNTRY even when the language is only spoken in a single country.
Just my guess.