CI CD pipeline for Gitlab

Hi,

I have to create a CI CD pipeline for automatic build & deployment of my react code deployed on app builder.

We are currently using Gitlab & would like to integrate the same with our CI CD pipeline.

I was just following this document - https://developer.adobe.com/app-builder/docs/guides/deployment/ci_cd_for_firefly_apps/ to create the pipeline, but got stuck when asked to create secret tokens within Gitlab. Can someone please guide me how do I create secret tokens in Gitlab. 

Thanks