Aside from using the /logout endpoint to end the users session in an OIDC app (this will result in a redirect), you can manually make a call to the Sessions endpoint to delete a users session via its session id (which you can get with a /sessions/me request) or via CORS in the same browser the user has a session.
As far as guides go, the one @phi1ipp linked to discusses the two different types of sessions a user can have and how to end each of them (they are handled independently so that if a user logs out of an OpenID Connect app, they are not automatically logged out of Okta unless you tell it otherwise): Sign users out