UTF-8 characters not loading in properly

Question

I have a school project that requires me to load a text file that includes UTF-8 characters like "ł,ą,ż,ź,ć,...", and then to do some editing on that text.

The problem is that, if I use SetConsoleOutputCP(65001), it loads the file correctly, but then if I try to use cin with ł, ą, etc then the characters disappear.

#include <iostream>
#include <fstream>
#include <string>
#include<windows.h>
using namespace std;

string opfile(string name){
    string line;
    ifstream myfile (name);
    string tekst;
    if (myfile.is_open())
    {
        while(getline(myfile, line)) {
            tekst += line + "\n";
        }
        myfile.close();
    }

    else cout << "Unable to open file";
    return tekst;
};

int main() {
    SetConsoleOutputCP(65001);
    string file_name;
    cin >> file_name;
    cout << opfile(file_name);
    string cos;
    cin >> cos;
    cout << cos;
    return 0;
}

This is whats inside the text file

ŁŁŁŁŁŁŁŁĄĄĄĄĄĄĄĄĄĄĄÓÓÓÓĆÓŹŻÓŹĆŹŻÓĆŻÓźćÓÓÓĆŹÓŻĆŻÓŹĆÓŚĄŚĄÓÓĄŚÓŚĄÓÓŚÓŚĄ

If I try to input this later, nothing is outputted.

I tried looking around, but everyone says the SetConsoleOutputCP() should work.