Beginner question about Deno on the web

Hi, I've been looking into Deno recently and I love everything I'm reading so far but something I'm confused about is: what does it actually mean to use Deno for a website frontend? Isn't Deno a runtime? What can it do on the browser?

I tried experimenting with SvelteKit and Deno by doing deno run -A npm:sv createdeno run -A npm:sv create, deno installdeno install, deno task devdeno task dev, but as I expected, all I'm still writing is normal browser code. Where does Deno come in?

Keep in mind that I'm not super well versed in a lot of web technologies so this might just be a misunderstanding on my part.