You can change a user's role, resend an invite, or deactivate a user at any time by clicking the ellipses next to the user's name and selecting your desired action from the menu.
When adding new members to your workspace, there are three options for the user's role within the workspace.
Options for roles:
Viewer can view all pages within a workspace
Member has all viewer permissions, plus the ability to edit all pages, and can share pages.
Admin has all member permissions, plus the ability to publish to community templates, as well as edit member permissions.
Owner is the user who created the workspace. They have all admin permissions, plus the ability to rename or delete the workspace.