Word frequency is steep in every language. A small core appears constantly and everything else appears rarely, which is why the first few hundred words are worth far more than the next few thousand.
Pronouns, होना and करना, the numbers to twenty, the question words, the common postpositions, and about forty everyday nouns. With these you can build sentences — badly, but genuinely your own — and that matters more than recognising a larger list.
Vocabulary size is a poor measure of ability, because knowing a word in isolation is not the same as producing it inside a sentence under time pressure. A learner with 800 words who speaks daily will outperform one with 3,000 who does not, every time.
Persian, Turkish, Indonesian, Malay, Swahili, Thai and Tamil all share words with Hindi through Sanskrit, Persian or Arabic contact. Speakers of those languages often start with several hundred half-recognisable words and never find out.
Reading an answer is one thing; being corrected while you say it is another. EkGuru tutors teach one to one from $6 a lesson, and most offer a trial.