token
Use CURL library to get token and lists in Magento2
'cURL' is a command-line tool that lets you transmit HTTP requests and receive responses from the command line or a shell script. It is available for Linux distributions, Mac OS X, and Windows.
To use cURL to run your REST web API call, use the cURL command syntax to construct the command.
To create the endpoint in the call, append the REST URI that you constructed in Construct a request to this URL:
https:////rest/
To pass the customer data object in the POST call payload, specify a JSON or XML request body on the call.
Step by Step getting the long page token for Facebook (90 days)
Here I will mention the way to get the token for Facebook Page
First of all try to check if you have crruent token and see when it will be expired by this link
Now the first step is to get the user token
OAuth 2.0 Playground link
https://developers.google.com/oauthplayground/ogleapis.com/token&includeCredentials=unchecked&accessTokenType=bearer&autoRefreshToken=unchecked&accessType=offline&forceAprovalPrompt=checked&response_type=code