i also can't find it in grub menu
Did you run grub update from within your main OS? If not, do so. Did you format the partitions correctly? It's a good idea to install to a separate partition instead of lumping Android x86 into an existing partition like their webpage says. Also, if you opted to install Android x86's version of grub, you may have to add items to the boot loader list manually. This is a long process so I won't go into detail here per forum rules. As for the black screen, it sounds like a driver issue. I can't give you any more than this as I don't know the technical details for Android x86. Try asking around on XDA forums, they'll likely have your answer. I'll give you a link.
Best of luck!