delete and rename user roles

When we first install wordpress, by default there is 5 user role created. Administrator, Editor, Contributor, author, and Subsciptions

Now what I want to do is delete 2 of theme and not have them showed up anymore when I try to add a new user.

And i like to change a name of it to something else.

i am also using the plugin user role editor. And i dont want it to be affected by this change. Can someone help me please?