title: How can I add roles to service account in GCP?
body: <p>I am using service account credential to deploy <code>cloud function</code> to GCP. I got a permission error:</p>
  <pre><code>Error: googleapi: Error 403: Missing necessary permission iam.serviceAccounts.actAs for $MEMBER on the service account
  </code></pre>
  <p>I open the service account permission in GCP but I can't find where I can add the role to the account.</p>
  <p>Below is the screenshot of the service account. There is <code>GRANT ACCESS</code> button but it is used to grant member access to this account. How can I add roles on the role list?</p>
  <p><a href="https://i.stack.imgur.com/eflGi.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/eflGi.png" alt="enter image description here" /></a></p>