|And I assume gcc is a compiler, but how to code on that!!?|
Yes it is a compiler and it can be used by all kinds of IDE, like Eclipse, KDevelop, CodeBlocks etc.
To use it from the shell, create a file with an editor like kwrite. If your file was hello.cpp, then compile like this:
g++ -std=c++17 -Wall -Wextra -pedantic-errors hello.cpp -o hello
g++ is the command for c++, the C command is gcc. gcc actually means gnu compiler collection, it can do other languages too.
then run the executable like this:
The ./ is kind of a security thing, it specifies to look in the current directory not in path environment variable.
It's worth reading the manual for gcc, there are a zillion options, but still worth it nonetheless.
Once you have a reasonable sized project you may want a make
file, but using an IDE is easier.
Good Luck !!