El Cap & Other Updates - very frustrating

I have been facing problem with MacBook Pro OS X 10.11 and iPhone 6 Ver 9.0.2 - AirDrop not working, update in App Store not working, Mail - not allowing junk mails deletion. El Cap is just very frustrating, very unhappy with present state of Apple update's. Software update on iPad & iPhone inspite of having internet connected says "Server not found " Try again