Is a 301 redirect the same as changing window.location?

I am a web developer who also works in SEO. I want to 301 redirect one page to another page. Is this 301 redirect for Google beyond what I write below for you?

In JavaScript:

<script> 
      window.location.replace("https://example.com");
</script> 

In PHP:

<?php 
    header("Location: https://example.com");
?>

Are these two 301 redirects, or do we have to write .htaccess in the cat file, for example?

Answer

You can not do this with JavaScript.

But you can use PHP as follows

<?php 
    header("Location: https://example.com", TRUE, 301);
    exit;
?>

Syntax header

header(header, replace, http_response_code)