Hello, how can i clean only part of the screen in C++? Please

Answer 1

There are no standard screen cleaning functions in C++. You would have to look up any commands your terminal implements for this purpose and forward them to the host environment via std::system:
https://en.cppreference.com/w/cpp/utility/program/system
Alternatively, to mimic such a behaviour, you can always insert a specific number of newlines, but that would depend on the terminal size.

Answer 2

You could take a look at the ncurses library: it's a robust cross-platform/terminal handler ;)
http://tldp.org/HOWTO/NCURSES-Programming-HOWTO/