Redirect http to https

I rebuilt my website and also made it https instead of http.

I’m trying to redirect my old urls to new matching ones but the links turn relative and so the redirection doesn’t work.

For ex. I want to redirect http://website-name.com/index.php to https://website-name.com/, but it turns to only /index.php which makes it https://website-name.com/index.php which doesn’t exist and so it doesn’t work.

How can I make it stay as http and not get cut out?

Thanks