Do you know how sometimes we learn a new word in one language but it sounds kinda similar to a word we already know in another language? That's kinda how Tamil loanwords in Sinhala work!
See, Tamil is a language that people speak in a part of India called Tamil Nadu. But, a long time ago, some people who spoke Tamil also moved to Sri Lanka, which is a country just south of India. And when these people started talking to the Sinhala people who already lived in Sri Lanka, they started using some Tamil words in their conversations.
Nowadays, even if people don't speak Tamil, some of these Tamil words have become a normal part of the Sinhala language. So, it's kinda like borrowing some cool words from another language to make our own language more interesting! Some examples of Tamil loanwords in Sinhala include "thambili" (meaning "coconut"), "ambulthiyal" (meaning "sour fish curry"), and "puliyodharai" (meaning "tamarind rice").
So even though Sinhala and Tamil are separate languages, they are very closely connected in some ways!