Install Arduino 1.8.13 (https://www.arduino.cc/en/software)
Select Arduino Mega as Board, ATMega2560 as Processor
Install the following Arduino Libraries (via Sketch -> Include Libaries -> Manage Libraries)
- OneWire 2.3.5
- DallasTemperature 3.9.0
After uploading you should probably clear EEPROM by opening Serial Monitor (with Baud 9600) and issueing:
M502
M500