I have installed ubuntu 14 in lenovoG50 80, after installing win 10 and installed it by erasing the hard disk completely by choosing an option from installing menu. After installing , I am unable to see disk in my home page.I want to do partitions and use it like in windows.What to do for it?
You should use
gparted for that, it's just like diskmgmt yet more powerful utility for disk partitioning.
BTW can you explain your situation with more details, you might not know English well because it's pretty hard to understand what you've written. I believe you're trying to dual boot Windows 10 & Ubuntu. Follow this guide.