Is it hard to change your eating habits after this.?? What do you eat what can you eat??

Depends on your level of motivation. Do you want to fail, or don't you?

Generally low fat, low carb, high Protein is recommended. So that's what I try to eat most of. I do have a little bit of junk food (sparingly. Small portions) every couple of weeks. Just because I love sugar. But most of the time I'm eating well. The band doesn't stop what you decide to shovel into your mouth. It only effects how much you can eat. The rest is all you.

So, is it Hard?

I think it depends on the person and their accountability and motivations.