@seednextsrl you typically don't use the access token as a login password.
The access token is what you present to other applications as proof that someone has logged in.
There are a few FusionAuth APIs you can call and present the access token as a means of authentication. They are marked with a little blue person.
Here's more about API authentication: https://fusionauth.io/docs/v1/tech/apis/authentication
Here's an example of an API which uses a JWT to authenticate: https://fusionauth.io/docs/v1/tech/apis/users#retrieve-a-user (scroll to the "Retrieve a User using a JWT" section).