REST API call in JavaScript/AJAX that authenticated Oauth2.0

Avg Bid (GBP)
Project Budget (GBP)
£30 - £250

Project Description:
I've got 3rd party system that supports REST API call via Oauth 2.0.

I need a page set-up (I can host this myself, just been the Code) that when visited takes a parameters from the URL (e.g. it gets the ID parameter from the following URL And does and REST call into the 3rd party updating an objects record (I need to update one field against the object using a POST).

I need to do this using client side scripts such as JavaScript, AJAX etc

I’ve trying building this myself but a limitation that I’m facing it that because it’s a cross domain update, so it looks like I need to use JSONP which I’m not experienced with.

Skills required:
AJAX, Javascript
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