partitions displaying more storage than my ssd really has

Hello everybody here,

I am new and not familiar with Mac OS, I have just bought a MacBook Pro retina 15" early 2013

16Gb of RAM 2.8GHz of i7 processor speed 8Mb L3 cash 751Gb of ssd storage

and installed high Sierra 10.13.4 on it, and am really happy to be part of Mac users

my first problem is that when I partitioned my ssd it started to show wrong storage amounts on each partition, and here how I partitioned it:

macintosh hd 150gb; Media 300Gb; backup 50Gb; Media2 250Gb

but on "about this Mac/storage" it shows:

macintosh hd 150gb; Media 300Gb; backup and Media2 are on the same container I think (which is another problem) and this one is showing 751Gb (the whole storage amount)

I searched for a solution and tried a command line "sudo mdutil -E /"

tried to drag and drop the partitions icon in "system preferences/spotlight/confidentieality" window

they said this will reindex the partition, but nothing works

the second problem that whenever I launch Boot Camp and hit the continue button it crashes, well, it says that it will report this to Apple... but still waiting, and Apple seems busy to fix that hhh

is there a solution