Yay! Congrats on getting dubia! I remember how hard it was to overcome the fear and get roaches. Now I have a colony that I’m fond of and has taught me to respect their icky little lives, as well as that of other gross bugs. (except larger spiders and all ants)
You’ll want to feed them the same stuff you’d feed any other bug - fresh greens, veggies, a little fruit. I also give mine some Repashy bug burger just to try and round out their diet. Giving the gutloading graphic to refresh your memory if needed.
You’ll want to keep them in a smooth sided plastic bin - they aren’t good climbers and can’t climb smooth or slick surfaces. Provide them something to hide in/under like egg crate, cardboard tubes. I keep my colony with a bioactive set up, but separate the babies out and give them a paper towel floor. Every week or two it needs cleaning. I just use water and paper towel to clean.
Your big handsome guy appreciates you overcoming your fear for him.