Can I have wifi at my tablet when home PC is off? I created home gr and home network. Use wind7?

You can turn on the personal wifi hotspot with your tablet if you have traffic plan. And you can create a hotspot with window 7 laptop,you can try to use My WIFI Router software or command it to be a hotspot,and you can check more detail from this link,http://www.mywifirouter.me/topic/how-to-configure-...

Most people use a home router as a wireless access point, so you would not need a PC to use that from a tablet or phone

(myself, I use my PC as the router/DHCP/DNS so in my case the wifi goes down if my PC is off, but that's unusual nowadays)