toki pona is a minimalist language made by canadian linguist sonja lang. there are around 130 words in the entire language. this restriction makes it so that talking about any complex topic involves breaking down what exactly that thing is. it's a super fun linguistic toy and also has an amazing community surrounding it.
toki pona saves a lot on words by expanding words' semantic spaces, essentially, giving words multiple meanings, and allowing them to be any part of speech. almost all words in toki pona can be nouns, verbs and adjectives.
pakalali suli
pakala li suli
the error is important (noun)
ilo li pakala
ilo li pakala
the computer broke (verb)
ona li toki pakala
ona li toki pakala
she was speaking with many errors (adjective1)
pakalaa
pakala a
fuck!
damnit!
bang!
keep in mind, as well, that no parts of speech are conjugated or declined in any way, meaning that you don't need to change any parts of speech depending on their role in an utterance; not even for tense, gender, number, aspect, etc.
jan li pali
jan li pali
a person is working
people worked
humanity will work
well, there are no direct answers to this. this relys mostly on what you call a "speaker" and also what you call "fluent."
but for simplicity's sake, the most recently released toki pona census data, there were ~1900 responses, so we can say that it's probably around there.
as for where it's spoken, i've noticed that most toki pona speakers also speak english, which we also use as a fallback language when we have trouble understanding each other.
you'll see crazy claims on the internet on how toki pona can be learned in 30 hours of study. and like... yeah, i guess it's possible? however, like any language, it takes time to master.
as for me, i learned all the words and sitelen pona in about a week, and could reliably translate whole documents, while consulting fluent speakers for tips. i actually translated the first episode of bee and puppycat as my first translation projects, after getting used to the grammar of the language. after a month, i felt pretty comfortable writing in toki pona, and even started using it in my school notes to make writing things faster. the word la is very useful.
but yeah, don't expect to get fluent (whatever that means) in that little time. toki pona is easy to learn, but tough to master.
if anything about toki pona intrigues you i'd highly recomend checking it out! you can look at my list of toki pona resources, including lipu sona pi toki pona by soweli Tesa, my favorite toki pona course, divided into 20 extremely short lessons.
you should also check out jan Sonja's books, i'd recommend getting toki pona: the language of good to start out. while it's a bit outdated, it's a foundational resource for learning the basics.
if you're into reading and you've learned a bit more, you could even try getting toki pona dictionary, a descriptive resource for toki pona, which documents and simply describes how toki pona is used, not how it should be used.
when you're comfortable consuming toki pona media, you can get jan Osu pi wawa nasa an official translation of the wizard of oz in toki pona.
1 alright, this one's a weird one. the phrase "toki pakala" is a noun with an adjective attached, and pakala has a lot to do with destruction or harm. and i can most easily translate this phrase as "broken speech" or "speech with lots of mistakes," but even then you could also translate it as "hate speech" when taken as "speech that harms"; the meaning can vary. see the "semantic space" of pakala.