Question: what is the difference between an openid connect id_token and an access token?
Answer: The id_token is used to identify the authenticated user, e.g. for SSO. The access_token must be used to prove access rights to protected resources, e.g. for the userinfo endpoint in OpenId Connect. access_token is useful to call certain APIs in Auth0 (e.g. /userinfo) or an API you define in Auth0.