My friend mother is here with B2 visa.At the airport she was given 2weeks limited stay with no AOS,COS and EOS.What can he do to extend her stay.Thanks

Here is the information and form that you need:
USCIS - I-539, Application To Extend/Change Nonimmigrant Status

Purpose of Form :
For nonimmigrants to request extensions of stay or changes from one nonimmigrant category to another nonimmigrant category. (You may also file this form online.) Please see the form's instructions for your specific nonimmigrant visa category. It is used by F and M nonimmigrants seeking reinstatement of status. It is also used by K-3/4 nonimmigrants to request extensions of stay and by persons seeking V nonimmigrant status while in the United States or an extension of stay as a V nonimmigrant.