I created a submit button with <input type="submit"> and that button appears in my language (Portuguese). Does it appear "submit" if the person who enters the website has a browser in English? Or it will appear the same for everybody and I should put the value="Submit"?
<input type="submit" id="send" aria-label="Submit">
Without some external translation mechanism (like a CMS), HTML won't automatically translate into other languages, what you see is what you get. Some browsers have functionality that will try to translate content, but that is on the client side and sometimes unreliable. If you want to ensure that your content will appear in the native language of a specific country, you'll have to add that functionality yourself.
On a modern browser, it should unless there is some language attribute.
