Welcome the Technical Support section. Help us in assisting you by providing us with a concise and descriptive elaboration of your issues. Be specific and if possible, provide us with a step-by-step instruction in replicating your problem.
Yes that is possible, you can change any jomsocial text inside this file language/en-GB/en-GB.com_community.ini, and if you wanna change the menu you can do it from Joomla Menu->Jomsocial toolbar