MONITOR Serial output gibberish

I tryed to install platformio on my Windows11 Pc but it is frusterating. As far as I can see, i con compile the upload looks also ok. When i try to look into the Serial Monitor, the output looks like rubish. I tryed differenr thinks like monitor_speed; upload_port but nothing works with the Serial Monitor. Any tips?

With regards,

Please show your code, the platformio.ini and a screenshot of VSCode with the serial monitor open.