Not sure if sarcasm that will likely instigate something or OP actually has an interest in Call of Duty and would like input.
A much more appropriate area to post such would be in the Community section.
Call of Duty is as simple as a shooter gets. Easy to play and rather enjoyable (sometimes addicting to some). Single player, IMO, is actually pretty good in terms of story/plot in most cases for Call of Duty. It can be enjoyable on the first go but there is no reason to go back and play it again unless you want the worthless collectibles. However, the single player is full of many cutscenes displaying sheer amounts of epicness that only Michael Bay could possibly approve of if he developed video games and it's extremely linear with no such exploration that can be done between levels, so I am not sure you'd like it.
The main highlight of Call of Duty however, is the multiplayer which is probably the more enjoyable, popular, and as I said before, addicting, part of the game. You create different classes with different equipment such as weapons and perks, and use them to go out and kill other players in various game modes. You progress and unlock more as you level up and complete challenges.
All in all, its a simple and easy game to play. Note though that there is an obvious difference between shooter and RPG. It has nothing in common with Skyrim besides being just as easy to play.
Yes, I took your question that literal because it's better than the alternative of what everyone is going to reply like.