how can i add or change dns server on ipad 2

Go to Settings/Wi-Fi. Tap the greater than sign ">" to the right of the network you want to set. You should see the settings for this network one of which is the DNS setting. You may have to set up a static IP address (Static Tab) for it to remember your DNS settings, since the dynamic setting (DHCP) will try to pull the settings from the router each time you try to connect.

Go to Settings > WiFi and touch the ">" next to your network name. This brings up the connection details one of which is the DNS server IP address.

not able to change my ip address of my office network to my home network ......so my internet is not working on my officw ip adress

Thank u for helping pople with low i.t i.q like me hehe