Help with overlapping letters

Hi! I would really appreciate some help on this, I'm trying to add a stroke to a word in Illustrator. I've converted said word to an object and then added the stroke I needed and aligned said stroke to the outside, but once I do the letters overlap and I'm not sure how to fix this. I wrote to my professor and he said that in order for the letters not to overlap I'd need to convert them into a single object with pathfinder. I've played around with pathfinder but still get the same result and I need a more detailed explanation on how to fix this. I've included a picture to give a better idea of what I'm referring to. Thanks in advance!