Your not making what your attempting to do very clear to subscribe to any group you either need to be invited if it is private or have requested membership and await a response from a group.what one are you trying to do
this is the google info on joining groups
Find and join a group
Groups are usually have a name that indicates the subject of the group, such as "cooking" or "music." To find and join a group:
From the Home screen, type a subject, such as "cooking" in the search field.
Press the Search button. A list of groups and messages is displayed.
Click on a group name, such as "Live music." The Topics screen appears displaying a series of topics. For more information, refer to Topics screen.
Click on the 'Join group' link. The Join group dialog box appears. Refer to About Group and Join Group dialog boxes.
Fill in the options on the Join Group dialog box.
Click the Join this group button. You are now a member of the group.
Note: An open group is configured to grant you immediate membership. A restricted group requires approval from an administrator before you are added to a group. A private group requires you to click on a link to request membership from the owner.