Looking for guidance

I recently started a new job as a Substance Use Disorder Professional Trainee in WA state. I am struggling feeling as though I dont fit with the way things are being run and im starting my 4th week with them tomorrow and im in turmoil. My credential is trainee because I am in school still and I have been given 0 of what was promised. In fact I literally have been doing another job instead of my own because there was another hire that was given my office. Im literally barely treading water and this is the 3rd time in a row I have had something similar happen and Im finding myself questioning if I want to stay on this path. If anyone has any pointers or experience/ encouragement type feedback Id be so grateful! -Katie