What is tab 3 10.1 ?? What web browser are we using? Internet Explorer? If so click the gear icon to the top right, then properties. Click Advanced, then click RESET, and check the checkbox. This will reset IE to factory. If you still can't get online then reboot and tap F8 repeatedly till you get the menu, then select Safe Mode With networking, can you get a webpage now? If so then you may have malware / virus.
Remove whatever AV your using and go to www.filehippo.com and download AVAST! or AVG, Then Download malwarebytes. Reboot (because you can't install in safe mode) and install the application and do a full system scan (By default it only does a Quick). AV doesn't pick up alot of malware, so that is what Malwarebytes helps...