Every Deployment you create in itopia CAS will logically connect to a Project in Google.
In other words, there will be a separate Google project for every deployment you manage in itopia.
Each of these projects will have their own permissions. A person that creates the project is the "Owner" of the project and has all rights to it including the access to launch the project/deployment to cloud in itopia.
If you want to add a team member to have access to the project, login to https://console.cloud.google.com/ and select IAM & Admin from the main menu in the top left.
Make sure you select the correct project.

You will get the list of allowed accesses for the project. You can add an admin clicking on the +ADD button.

Then type the email address of he person you are adding and select the Role as Project Owner. This type of access is needed if the new admin will launch the deployment to cloud from itopia portal.

If other type of access is needed, have a look here for more details about the Roles.