Global Reader role - Not working to access Sharepoint Admin Portal

Thank you grant_jenkins​ for responding to the question, had got a similar responses from other sources as well. Seems like with the Global Reader role, certain privileges are available through Powershell to the Sharepoint Online. One of the responses that I had received also added "This is a tool using PowerShell to execute command, and Global Reader can only access to specific API that specify as "Read" (Get-) like get list of sites, get list of design, ..., not modify command."