You are welcome. I'm glad it is working now.
The "esp32" boards platform has a very unusual configuration where it can identify the port of ESP32-based boards as "ESP32 Family Device". This is convenient for the Tools > Port menu as it makes it easy to see which of the serial ports is the port of your board in the case where multiple serial ports are present on your computer. However, the way the "esp32" boards platform developers accomplished this is to create a "dummy" board definition, which doesn't actually work. This means that if you select that port from the menu on the Arduino IDE toolbar, it configures Arduino IDE to use the dummy "ESP32 Family Device" board definition, which causes compilation to fail with this cryptic "{build.partitions}.csv' nicht möglich: Datei oder Verzeichnis nicht gefunden" ("{build.partitions}.csv: No such file or directory") error.