Welding Tips and Tricks

Hi I am new here and also a beginner in welding . I have been offered the above welder that is old. I don’t know anything about these and been told it needs a new torch but not sure which ones will fit .Do the euro ones fit with the adapter? . Also wot gas is best for mild steel . And not sure the min and max size mig wire they can take .Any help will be much appreciated. Thanks .