Looks like you've messed up some terms:
I was trying to enable mobile hotspot function, so I could enjoy internet from my PC adhoc wireless network
First: the mobile hotspot function is to share your Android device's mobile Internet connection to other devices not having Internet on their own, e.g. a tablet or laptop, via WiFi.
Second: only few Android devices support ad-hoc networks. There are solutions, but all of them require your device to be rooted.
Third: if you wanted to use your PC's Internet connection on your Android device, that would be reverse-tether, and again require root to be established.