I need a simple and accessible explanation because I still don't understand it well yet. Is there a free and easy way to redirect my domain to any site? Thank you!

You can use the refresh meta tag to achieve this. Additionally, you have the option to specify the exact number of seconds for the transition delay if you prefer a gradual redirection. Another alternative is to create a basic HTML page that includes a message indicating the site has moved along with a corresponding link.

I don't comprehend the reason behind it. Your domain name is not being promoted, and no one is aware of its existence. There will be no traffic or visits, except the ones you generate yourself. So why should you pay for a redirection service?
Perhaps there is a misunderstanding here?
Furthermore, if your domain is already popular and well-promoted, it doesn't make sense to give it away. Instead, you should consider monetizing it for yourself. Moreover, if you choose to redirect it, all the progress made will quickly be lost. In any case, I fail to see the logic behind this decision.