Windows 7 PC not connecting to DNS

I tried following the instructions but my computer just doesn’t connect to nslookup gives UnKown as the output and the only thing I am able to access is and some variant of that like I cannot acess google or any other website once I change the DNS on the PC to and I can connect fine though the app for android on my phone but I cannot find any resource or troubleshoot the problem on windows 7. Seems that nobody has this issue except me. I am a novice so I don’t really know what I should do or post here so someone can help me. Please tell me what diagnostics I should run and post here. Really appreciate any help!