No, real magic is nothing at all like the magic in Harry Potter or other fantasy novels and films. It certainly requires more than a few words and a swish and flick of a wand.
Yes, it is possible to curse someone. Whether it works or not depends on quite a few factors including whether the person casting the curse knows what they are doing.
You may want to look into thoughtforms. You can create one with the specific purpose of protection.
But the magic you see in books and movies are more often than not fantasy