Shows some of the screens you see with advanced mode. Did you try that.
Best to run Boot-Repair from Ubuntu live installer of version you have installed. The Boot-Repair live ISO is not as current as the ppa most of the time.
https://sourceforge.net/p/boot-repair/home/Home/

You run fsck or e2fsck on formatted partitions like sda2, not a drive like sda unless you formatted an entire drive which is not recommended.
There also is dosfsck for FAT32.
See
man fsck
man e2fsck
man dosfsck