Offering help with learning C++

i guess im to late and 16

im learning C++ atm ( no really now im learning C++) im trying to make
my first program, im also reading a book but i'm learning now from lessons that i have downloaded from internet .

i need some answers for my first program.

thanks if you accept me

while i was coding something, i got this error, can you give me any idea how to fix it??

thank you