How to add JQuery in html?

I want to code with jQuery in my html website, but when I type any jQuery code : it doesn’t work. many tutorials on youtube say that I have to download the jQuery file, can you please explain me clearly ? :thinking:

I think that jQuery is usually done along with JavaScript, so you may need a script tag to be able to include jQuery code:
maybe:
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.5.1/jquery.min.js"></script>

and also a script tag to use a file (like a JavaScript file) if you have your code in a separate file,
or write the jQuery stuff with the JavaScript code between <script> and </script>