Yes bro b-12 will def work, it helped me when I was taking anadrol and had zero appetite. You may also want to check the sources here as I know a few that has products that can help with appetite.

avoid eating foods that are very acidic, like carrots, orange juice, tomatoes, lemons, limes, and other citrus fruits......since a high level of acid tells the brain to slow digestion down, which will result in a lot of food just sitting in your stomach, killing your appetite. don't eat a lot of foods that contain a lot of sodium, like frozen foods and canned soup. Again, sodium also tells the body to slow digestion down, and, again, taking away your appetite. You want to eat smaller meals more frequently throughout the day to stretch your stomach. You can definitely try Digestive Enzymes and even Vitamin B-12

You could also try some Vitamin B12 injections.

try some digestive enzymes. i have always had problems eating. same as you, i never wanted to eat, never felt hungry, always hated the thought of eating. digestive enzymes really helped my appetite a lot.