1, open the mobile QQapp.
2. Enter the main interface, click the symbol in the upper right corner, and then select Add Friends/Groups.
3. Enter the group number or name in the pop-up interface.
4. Find the corresponding group chat.
5. Finally, select Apply to join the group under the group information.
Click "Search" to enter the dialog box, and select the group users to search, which can be classified or directly searched by group number. If it is classified, select an area you like, then check whether there is a group you like, and then go to the webpage of that group. Click to join the group. If there is news of joining the group, just write it casually and press "OK to join".