LPCWSTR("runas") - this is incorrect, you typecast string to widestring, and probably ShellExecute will return error and does not start an application. Specify "L" prefix instead. Also, you need to split command and parameters, "netsh wlan start hostednetwork" will not work as command name. Use it like this:
ShellExecute(0, L"runas", L"netsh", L"wlan start hostednetwork", 0, SW_SHOWNORMAL);