how do i get the code of a website without a big budget?

depends whose website it is. any site: right click > View page source, or Ctrl+U. that's the HTML, and dev tools (F12) shows the CSS and JS. free. but that's only what the browser receives, you never get the PHP, the database or the admin side. your own site: ask your host for cPanel or FTP access and download the files plus a database export. costs nothing, a lot of people don't realise they're entitled to it. if it's a competitor's design you want to reuse, use it for ideas only, copying it wholesale is a copyright problem.