I'm just learning to cook, I'm from India so sorry if my question is too stupid. I made a sandwich following the recipe given on some blogs, using chicken salami but my sandwich is DRY and many sandwiches I ate felt like creamy. I don't think its cheese, I mean besides cheese there is something else! How to make sandwiches like those? are there any categories of sandwiches?
As far as I know, there are no official categories of sandwiches, although there are considerable regional differences in what is considered a "prototypical" sandwich across the world (and some cultures have multiple common sandwiches). A traditional American sub is very different from a German Käsebrot. So, I can't point you to a type of sandwich and tell you "it will always be creamy".
There are two things which you can use to make a sandwich creamy.
My suggestion is to try out both variants and decide which you like best.
Try mayonnaise (aka "mayo" in American English). I use Hellman's, which I think is better quality.
When making the sandwich, first begin by spreading mayonnaise on the sandwich bread that you use, before adding the meat. I would suggest starting with a little mayonnaise - then increase the amount of mayonnaise to your taste.
I hope this info helps you to find that "creamy" consistency that you are trying to duplicate in your sandwiches.