What is better to show 404 error on the page or redirect to 404?

Question

Search Engine Optimization

What is better to show 404 error on the page or redirect to 404 ?

For example:
1) https://site.ru/page_1.php
or
2) https://site.ru/404

Answer 1

From a Web development point of view, according to the HTTP standard, the server should return 404 if the page is not found (without changing its URL). A 301/302/307/308 redirect is done when you know exactly where the page was moved to.
A redirect to a page that will give the browser a 404 misleads the visitor - it is not clear which URL is broken and cannot be corrected manually.
From the point of view of Search Engine Optimization - it is necessary to give "200 OK", a typical splash screen "Page not found" and put a link from it to the main page of the site (or mini-menu for sections).
Search engines "glue them by content" into one page, but this will allow you to pick up the static weight of external (and internal) links to such pages not found.

Answer 2

Probably redirect. It will be convenient to edit the 404 page.

Answer 3

Oh great SEO) Let's say there was a str1 page (search engines indexed it), you changed its URL - it became stranica1. Therefore, when a person visits str1, he should see a 404 error - the page does not exist. Then you have several ways:
1. To score, the search engines will find stranica1 after a while and throw str1 out of the search. - an option when the page has no positions and links (both external and internal)
2. Make a 301 redirect from str1 to stranica1 - when the page has positions or links (both external and internal) - and this way we will get rid of 404 errors.
3. On str1, hang 410 response - "page deleted" and send it manually for indexing stranica1 - an improved version of the 1st option)