Is posible to redirect a few URL?

i'm making this website using wordpress as headless and using gatsby in the front-end, i pass the information using the api

I have the wordpress in a URL example ap-backend.com and the front-end in other URL which is the main url of my page for example ap.com

For avoid people try to see and check the back end i made the follow function to redirect to my main url

function redirect_website() {
        
        if ( ! is_admin() ) {
            wp_redirect( $main_website, 301 );
            exit;
        }
    }

where the $main_website has the main URL and if someone try to check ap-backend.com this redirect to ap.com

Right now i want to create a newsletter using the rss feed and as you can imagine if i use the ap-backend.com/feed/rss i see is the main url, so my question is, can i have the redirection to all url except the url of the feed? (ap-backend.com/feed/rss) or can i redirect to have that info or ap.com/feed/rss i see that i can do it in the .httaccess but this is a validate opcion?

Thanks for the help guys!