How to display specific custom post type in RSS feed

Is there any way to display posts within an RSS feed from a specific custom post type out-of-the-box?

I am in the same boat here.

I am trying to get a feed of my custom post type “auction.” I go to this link: https://uniimi.com/feed/?post_type=auction and it is not a feed, it is the full content of the most recent post.

If you look at https://uniimi.com/custom you can see that there are more than one posts of this type.

Any thoughts?